Official ICE Forums
Systems & Settings => Rolemaster => RMC/RM2 => Topic started by: Urbannen on November 10, 2007, 12:48:31 AM
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Maybe this seems crazy, but I feel that the effects of wearing armor should be switched for Mentalism and Channeling. I'm not quite sure why clerics and paladins should have a harder time wearing metal armor than psychics and mindbenders.
An explanation via flavor text: Only the manipulation of Essence is disrupted by the wearing of inert materials. Channeling bypasses the Essence by bringing in energy from another dimension. Mentalists only channel the "Essence" that resides in their own psyches. Since the flows of magic are going one way - out - they can wear more inert material without disrupting the flow of magic. Essence users have to bring in energy and then push it out again, and any inert material interferes with this process.
I'm not sure I like the idea of animists and rangers wearing metal armor, however...
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Paladins have a great bonus to the Trascend Armor skills that helps them a lot in casting while wearing metal armors. You could give clerics a similar bonus if you want them wear chain and plates.
Also, remember that mentalists only get the penalties if they wear helmets: I don't see this limitation very fitting for the Channeling realm...
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Paladins have a great bonus to the Trascend Armor skills that helps them a lot in casting while wearing metal armors.
That's right.
You could give clerics a similar bonus if you want them wear chain and plates.
I do not recommend that, the problem is that D&D has created a wrong image of cleric, it is a cleric not a fighter!.
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Yes, clerics should wear the robe of the Mendicant monk. :D
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Paladins have a great bonus to the Trascend Armor skills that helps them a lot in casting while wearing metal armors. You could give clerics a similar bonus if you want them wear chain and plates.
Also, remember that mentalists only get the penalties if they wear helmets: I don't see this limitation very fitting for the Channeling realm...
To add to my post, Channeling casters would not receive a penalty when casting with helmets, although Mentalism casters still would.
I think the fact that Paladins have to have such a bonus to Transcend Armor shows a basic flaw in the system.
If I remember correctly, the example illustration of the cleric in RMSS showed a dwarf in metal armor. And if a cleric isn't a fighter, than how is a Mentalist a fighter? Also, the armored cleric may be taken out of D&D, but so are the RM cleric's spells. Like in D&D, RM clerics don't have great combat spells (or at least they don't have many). And obviously RM clerics aren't dressed as mendicant monks since they can still wear lighter armors.
It doesn't make a lot of sense to me for Mentalist character classes to go around in heavy armor, at least, less sense than for a cleric to do so. The mentalist class has some of the most decent individual combat spells, especially at lower level. And don't they get their power from focused meditation? Plus it seems better to limit the Bard to light armor.
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I think the idea is that channeling magic does come from thier god but they have to cast it like an essence user. The essence user needs to be in contact with the essence field to cast his spells. And the ment user has internalized the magic some how so he only has problems with his head being covered.
But that said if you are the GM try it out. Make the switch or reduce the pelaties and see how it goes. If it works ok then keep it if it does not make up some magic effect and have the bonus go away.
MDC
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First a few quotes from RMC Spell Law:
"It was discovered that it was possible to make a direct link or bond with the souls or spirits of certain mortals. This link allowed the immortal to gather the dangerous raw essence, and send it down these channels in far more controlled and manageable flows. This new, weaker but more manageable form of casting, combined with intervention from these powerful beings, meant that more mortals could become casters, and being one became far less dangerous." RMC Spell Law page 12.
"Channeling casters draw their power from their deity, so local fluctuations in the essence field, or even the absence of a local essence field will have no effects on their ability to cast. Metal seems to interfere with their divine connection, so when casting a Channeling spell, the caster must wear no metal armor, ... . More importantly their ability to draw power is based on their relationship with their deity, so their actions and behavior can have serious impact on their ability to draw power or cast." RMC Spell Law page 30.
"Channeling represents the powers of the deities of a given world ... . A spell user of this realm may draw their strength from their respective deity, and often does not require that deity’s cooperation ... . More powerful
and significant spells, however, such as death spells and the revival of the dead, might require the active consent of a deity (depending on the world system)." RMC Spell Law page 89
The Realm of Channeling is one of the most misunderstood of the three (four with Arcane) Realms. I feel most of this confusion comes from the Channeling Companion which drastically altered the canonical understanding of the realm. Markc is right in that the power from the deity is still essence from an outside source, but unaffected by the local flows. It is not the power of a god granted to a mortal but a resonating sympathy between the object of worship, the Cleric (or channeling using subject) and the flows of essence through that sympathy (channel). Metal seems to interfere with that flow of essence similarly to essence users. The channel (sympathy) is a passive aspect between the deity and the channeling users until higher level spells contact or involve the deity to acquiesce, at the very lest, in the ultimate effect.
The Paladin’s efficacy with Transcend Armor is more an occupational hazard than a flaw in the system. To fulfill his role, a Paladin needs this affinity and learns it. The passive nature of the channel means that the deity does not take a direct interest in overcoming the limitations of the realm.
Powers that come directly from the deity might not have those limitations, as they are direct manifestation of divine power and might, and not a passive sympathy (channel). The recipient of these granted abilities may not even have the capability to cast spells (low scores), but is granted special abilities from the deity represented through Talents, Backgrounds or Gifts.
The sympathy between the deity (or subject of worship) and the channeler would be broken when the channeler greatly transgresses against the ethics, morals, ideas and/or goals of the deity. He would lose access to the essence from the deity.
Metal interferes with essence users, channelers and even mentalists when worn on the head. Each of these interferences relates to the source of essence, how it is processed and used. In channeling, it does not deal with the will of the deity. The world system of each gaming group could adjust these accordingly, but as canonically represented within the rules, metal interferes with essence regardless of the source or application.
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Not quoting any books but another sticky point is do channelers pray for thier power and then use it or do they patation the diety during the act of casting to get the power. This IMO has a very dramatic impact on how your game is played.
MDC
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... do channelers pray for thier power and then use it or do they patation the diety during the act of casting to get the power. This IMO has a very dramatic impact on how your game is played.
MDC
It would seem that neither does the channeler pray for power nor directly petition the object of worship during casting (though the channeler would invoke name and might of the deity during casting). If prayer were part of the cultic aspect of the deity’s ethos or worship, then the channeler would pray, as part of maintaining the sympathetic resonance between himself and his source of essence, just as if sacrificing a small bird on a specific holiday could be incumbent to the channeler to maintain the channel between the two as open.
The need for words and gestures in the casting of spells does not open the channel but takes advantage of the sympathetic relationship (channel) between the caster and the worshiped that has allowed access to the power to cast spells (aka.: power points). The channeler maintains the channel though devotion to ideals and not through direct requests for power. The aspect of prayer used to request boons from a deity would be more in line with granted powers (Talents, Backgrounds and Gifts). This is the confusion caused from the Channeling Companion. That book focused more on granted powers and changed the concept of Channeling as a passive conduit of essence to a divine vending machine of powers, miracles, and abilities.
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Some of this has been discussed in the past - way back in the archived archives...!! ;D
- Magic and Metal (http://www.ironcrown.com/forums/topic.asp?ARCHIVE=true&TOPIC_ID=871)
- Channeling, Armor, Balance (http://www.ironcrown.com/forums/topic.asp?ARCHIVE=true&TOPIC_ID=1121)
Maybe you can find something useful in those discussions...
//K
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I guess it all depends on how you envision magic working.
However, I can't think of any good "flavor" reasons why mentalism spell-casters should be able to wear metal armor. It doesn't seem at home in bards, magents, mentalists, or seers.
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I guess it all depends on how you envision magic working.
However, I can't think of any good "flavor" reasons why mentalism spell-casters should be able to wear metal armor. It doesn't seem at home in bards, magents, mentalists, or seers.
IMO it would be that they generate their own power by wlaking through the power field of the planet. Sort of like the idea of a light bulb lighting up around high voltage power lines eventhough it is simply held in a persons hand. If thier head is covered by metal they cannot access the power as easily.
But as I said above you can change it at your leasure as it is your game.
MDC
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It is not the power of a god granted to a mortal but a resonating sympathy between the object of worship, the Cleric (or channeling using subject) and the flows of essence through that sympathy (channel).
Maybe in your campaigns, but this is not the only way that channeling can be seen... fortunatley RM is not d&d and so we may choose how to see it!
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It is not the power of a god granted to a mortal but a resonating sympathy between the object of worship, the Cleric (or channeling using subject) and the flows of essence through that sympathy (channel).
Maybe in your campaigns, but this is not the only way that channeling can be seen... fortunatley RM is not d&d and so we may choose how to see it!
1) Yes, I understand that rules can be changed and have reworked magic to fit campaign worlds too.
2) I understand that this is in the house rule section, and I did say that a gaming group could change the system to fit their needs.
I was merely explaining the method of Channeling as represented within the core rules, highlighting a deviant form of channeling represented from optional rules (Channeling Companion) to assist in explaining why metal interferes with the flow of essence from a deity through the sympathetic channel to the worshiper. To completely understand how metal impedes channeling, it is necessary to understand the source of power, the component of the power, means of delivery and the process of application of power. Understanding the whole mechanism enables the gaming troupe to most effectively modify, in this case, the Realm of Channeling to their needs.
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I was merely explaining the method of Channeling as represented within the core rules, highlighting a deviant form of channeling represented from optional rules (Channeling Companion) to assist in explaining why metal interferes with the flow of essence from a deity through the sympathetic channel to the worshiper.
But, core rules don't say anything about "resonating sympathy". I think that this is your interpretation of the rules. It's a good interpretation, but not the only one that can be given.
And, actually, in the RMFRP core book it's clearly stated that
Channeling is the power of gods as channeled throught their followers
and
It is religious in nature and indipendent of the Essence
So, by the core rules, Channeling has little do to with Essence and it's the power of a god "channeled" or bestowed upon a mortal.
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I was merely explaining the method of Channeling as represented within the core rules, highlighting a deviant form of channeling represented from optional rules (Channeling Companion) to assist in explaining why metal interferes with the flow of essence from a deity through the sympathetic channel to the worshiper.
But, core rules don't say anything about "resonating sympathy". I think that this is your interpretation of the rules. It's a good interpretation, but not the only one that can be given.
And, actually, in the RMFRP core book it's clearly stated that
Channeling is the power of gods as channeled throught their followers
and
It is religious in nature and indipendent of the Essence
So, by the core rules, Channeling has little do to with Essence and it's the power of a god "channeled" or bestowed upon a mortal.
I will concede that in RMFRP that it clearly makes your point. I was unaware that RMFRP had deviated from RM2 within the Realm of Channeling so completely. I had always assumed that was the fault of Channeling Companion. However, within RMC my point stands even if you take umbrage with my terminology.
“It was discovered that it was possible to make a direct link or bond with the souls or spirits of certain mortals. This link allowed the immortal to gather the dangerous raw essence, and send it down these channels in far more controlled and manageable flows.†RMC Spell Law page 12
While Character Law repeats what you have quoted (page 38), Spell Law explains further that the deity is gathering essence, even though the Channeler is independent of the essence flows. Without an analogous, clarification within RMFRP (one that I did not find), you are correct in RMFRP. The disagreement between us is one of system and more akin to a misunderstanding. I am not sure which of the two systems the originator of this thread uses.
Yet, that makes the issue Urbannen has very problematic if he uses RMFRP. The internal logic of why metal affects channeling casters is lost. If the Realm of Channeling (in RMFRP) is granted powers then is it not the deity’s responsibility to over come the resistance of metal and what of deities of the earth, metal and related spheres. (Yet, another reason I don’t/won’t play RMFRP.)
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I didn't realize that you were referring to RM2 rules ;D
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I generally agree with Setorn's view in terms of how I run things in play.
The only flaw in overall logic per canon, is the channeling skill.
A lot of discussion has gone on in terms of "Battery" or "Transformer". . .i.e. does a caster have a pool or battery of power they cast from, or are they a transformer of essence, with a limit of how much power USE they can do in a day?
The channeling skill makes the strongest single argument for the "Battery" version. . .caster A sends 10 PP to Caster B. . .and there are rules relating to the max power you can hold, and burnout and the rest.
The transformer version makes no sense if you have a 100 PP limit, cast 100, receive 100 from other casters, cast 100, repeat. . .Play a high ranked priest with a large church, or a mage guild master, or a central power of a group of mentalists, and you can have situations where your PC could cast/recharge/cast/recharge essentially an unlimited amount of PPs (Until you blow a casting roll or exhaustion stops you.).
So that skill seems to enforce the "Battery" logic. . .you absorb power, and it fills up a virtual "container" with power to use.
The armor limits are all tied to magic use, not PP gain. The essence user will absorb PP via their aura, the mentalist user withh absorb them into their mind, and the channeler will absorb PP via their soul or spirit, regardless if you bury them under a pile of metal. . .the point where metal blows things seems to lie in casting, not drawing power.
It's merely my opinion, but by that logic, the essence user is weaving raw essence into spells with their whole aura, their whole body. Channeling users are also using their whole body aura (they use their soul to manipulate their aura to cast.) mentalism users are only using the aura in the vicinity of their head to weave spells. (Which in my opinion is why their flows tend to be more subtle and objectively a bit weaker in physical effects.). . .metal doesn't interfere with gathering power, it interferes with weaving the raw power into spells. . . .Essence users are doing a raw power-aura-spell weave, so metal blows them the most. Channelers are doing power-soul/spirit-aura-spell weave, so metal hurts them less as they have more control. . .mentalists weaves are focused in the head, so only head metal hurts them. . .that's just my explaination, but it does fit all the game mechanics in the books as is without mods.
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A lot of discussion has gone on in terms of "Battery" or "Transformer". . .i.e. does a caster have a pool or battery of power they cast from, or are they a transformer of essence, with a limit of how much power USE they can do in a day?
The channeling skill makes the strongest single argument for the "Battery" version. . .caster A sends 10 PP to Caster B. . .and there are rules relating to the max power you can hold, and burnout and the rest.
The transformer version makes no sense if you have a 100 PP limit, cast 100, receive 100 from other casters, cast 100, repeat. . .Play a high ranked priest with a large church, or a mage guild master, or a central power of a group of mentalists, and you can have situations where your PC could cast/recharge/cast/recharge essentially an unlimited amount of PPs (Until you blow a casting roll or exhaustion stops you.).
So that skill seems to enforce the "Battery" logic. . .you absorb power, and it fills up a virtual "container" with power to use.
(I seldom say this) I am confused with this section of your post LM. Where are you getting the limits on how many power points or how much power can be channeled per use of the Skill (I know the percentage of power points spent (channeling ranks of the sender) and the percentage gained (channeling ranks of the recipient) limitations). You seem to be suggesting that there is a maximum amount beyond the ranks of the sender and the recipient. Likewise, are you limiting how often the skill can be used? If you are, where are you finding that limitation?
I have read and reread the sections on channeling in Spell Law and in Character Law for RMC, and I do not see these limitations?
That said I feel (opinion now too) that the source of each of the Realms is the same primal, raw or Arcane essence, but the manner in which the primal essence is filtered and not the application of that essence determines how types of material and/or material location inhibit its application. Otherwise, for some spells that if the target were wearing armor, that armor would likewise impede the application of the spell.
Essence is filtered through the aura of the spell caster and is most closely related (opinion) to raw essence. Channeling is filtered through the caster’s focus of worship (as maintained through cultic praxis, and devotion). Mentalism is filtered through the charisma and mind of the caster and is the furthest from primal essence. The process of filtering changes the primal essence and that is where the limitations are acquired. Those limitation relate to how that power can be used. How primal essence is filtered explains both armor limitations and the limitations of the Realms (Channeling good at healing, Essence elemental spells, etc…). Again, the filtering process changes primal essence into channeling power, essence power and mentalism power. How one manipulates one’s aura during the casting of a spell seems less important to the overall limitations of the realms than the type of filter used.
As to the channeling skill and how it might relate to this: The skill is further refining power for use with another caster. The channeler (skill) becomes another filter and the recipient becomes another that explains why the power points are reduced twice. The sender is not casting a spell and metal does not affect the channeling when sending merely power points. Once the recipient receives those points and uses them to cast spells metal affects the casting.
LM, this topc may need to be split...
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I'm saying that there are two ways of looking at magic.
Caster is a transformer. . .i.e. the caster has 100 PP, they can transform 100 PP of exterior essence into spells. Their limit is a limit of use.
Caster is a battery. . .i.e. the caster has 100 PP because they have a 100 PP sized "bucket of PP" associated with their character.
I beleive Battery is true. . .and that channeling proves it. You have 100 PP, you cast 100 PP, you have now "used 100 PP in 24 hours". . .I channel 100 PP to you, you can cast another 100 PP. . .this blows the whole logic of the "Transformer" model.
I beleive in fact that this proves the battery model.
That might seem off topic, but it's the basis for the next step in my logic
OK, now, armor in no way inhibits the ability to gain PP. . .if you sleep soundly or meditate successfully wrapped in metal, you still gain PP. (Essentially, the only way armor can prevent PP gain is if it makes you so uncomfortable you cannot sleep or meditate.)
So, armor has no effect on the ability to draw power, for any of the three realms. You can refill your battery regardless of armor worn, metal or otherwise.
Armor only affects casting.
Going from the primal essence field to the cast spell, the power does:
Source - Caster - Spell
Your comments above seemed to say that armor inhibits source-caster interface, I think the rules don't really play out that way. I think armor has no effect on the source-caster interaction, I think it only has an effect on the caster-spell side of things.
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Source - Caster - Spell
Your comments above seemed to say that armor inhibits source-caster interface, I think the rules don't really play out that way. I think armor has no effect on the source-caster interaction, I think it only has an effect on the caster-spell side of things.
Actually, I agree with you that metal does not interfere with power acquisition. However, I believe the process is a little more complex than source-caster-spell.
To me the process follows:
Source (primal, raw Essence) – Filter (Aura, Deity or Charisma (Mind)) – Caster – Spell
Converting primal Essence through the filter changes it to more usable, but more limited power, when that change takes place the power that the caster uses reacts to the world around it differently depending on the Realm. It is not how the caster casts that makes it interact with the environment differently, but how it was filtered. The Channeling skill implies that all transfers of power (filters) are unaffected by metal regardless as to how it was filtered. When that filtered primal essence is used to cast it reacts according to the limitations that the filter imposed though the nature of that filters Realm.
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I think Lord Miller's interpretation is definitive, based on the rules set.
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There is definitely a filter effect, and a change of "Flavor" in that you cannot channel power between realms. . .although you can transform it. A priest cannot channel to a magician, but they could channel 100 PP to a sorcerer, who channels it to a magician. . .somehow hybrids can not only use both inputs, they can freely change it between their flavors. (This is also I think why hybrids dont have 2 distinct power pools.)
The flavor element is also seen in adders and multipliers.
There are no armor mods I know of to the channeling skill, so you can trade around the filtered/flavored power freely regardless of armor or equipment.
It's only at the stage of spell weaving that metal problems pop up.
I agree that the model is a little more complex, it's more:
Chan: Raw Essence - Diety - Caster - spell
or
Ment: Raw Essence - Mind - Caster- spell
or
Esse: Raw Essence - Aura - Caster - Spell
with only "Arcane" being:
Raw Essence - Caster - Spell
no filter at all.
OTOH the "arcane" element of innate casting would seem to suggest they have something like an organ in their brain that does the filter work for them. (since innate is proto-arcane, but seems about as safe as essence.)
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with only "Arcane" being:
Raw Essence - Caster - Spell
no filter at all.
OTOH the "arcane" element of innate casting would seem to suggest they have something like an organ in their brain that does the filter work for them. (since innate is proto-arcane, but seems about as safe as essence.)
I agree that Arcane as written in RoCo I did not seem to represent the danger involved. I hope that the new RoCo I will fix that. I did in my games.
somehow hybrids can not only use both inputs, they can freely change it between their flavors. (This is also I think why hybrids dont have 2 distinct power pools.)
I ran a low magic game where hybrids did have to have two pools of power and their base list needed double power points (one from each realm) while open lists did not, but did need the correct type of power. You should have seen how many players chose Pure or semi-users in that game.
There is definitely a filter effect, and a change of "Flavor" in that you cannot channel power between realms. . .although you can transform it. ...
The flavor element is also seen in adders and multipliers.
There are no armor mods I know of to the channeling skill, so you can trade around the filtered/flavored power freely regardless of armor or equipment.
It's only at the stage of spell weaving that metal problems pop up.
Yet, what I am saying is that it is not the weaving that makes metal inherently problematic, but wholly the flavor added from the filter. All transfers/acquisitions of power are unaffected by any type of barrier as they are during weaving. Acquiring power from a deity or the essence fields/flows and channeling the skill are unaffected by metals. Nevertheless, the more subtle controlled application of power through spell creation/weaving are affected by metal depending on the realm of power and the flavor of that realm as colored by the filter (wow, what a passive voice sentence).
I feel that if were attempt to divide casting down it looks more like this:
Source - Fliter-Caster-weaving-effect
Chan: Raw Essence - Diety – (the transfer applies flavor) Caster – weaving (limitations due to flavor applied (Metal, inherent limitations due to realm) - effect
or
Ment: Raw Essence - Mind - (the transfer applies flavor) Caster- weaving (limitations due to flavor applied (Metal, inherent limitations due to realm) -effect
or
Esse: Raw Essence - Aura - (the transfer applies flavor) Caster – weaving (limitations due to flavor applied (Metal, inherent limitations due to realm) -effect
(Ignoring Arcane for the time being)
What I am positing is that it is not how the aura is used to weave the spell (which seems clumsy to me), but the flavor added to the power during the transfer.
Our ideas seem valid in view of the canonical rules and LM, I understand your opinion, but for reasons of clarity and elegance, I disagree. Nonetheless, we seem to be debating how many angels can dance on the head of a pin. However, I am enjoying myself doing it.
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Flavor might explain somewhat the variations between essence and channeling, but not mentalism.
Mentalists only weave spells with their head. . .so metal on the head is all that matters.
E and C are almost the same in metal response, but Essence is screwed up by dead organic matter also. Mentalism is also messed up by dead organic, in that it's not just "no metal helm" it's "No helm at all".
On one hand, this is likely game mechanics ala "Don't let mages wear armor", but if there's an underlaying logic to it, it likely ties into the "how" of casting.
How mentalism stands apart, seems to suggest similar logic is the cause for the other two.
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Sorry, it has taken me so long to respond, LM, but I have been in dress rehearsal for week for a play.
I would like to review on what we seem to agree:
1) The acquisition/transfer of power is not impeded by any material barrier.
2) The filter changes the nature of the raw essence making it more usable and safer.
3) The process of spell casting can be interfered with by material barriers.
What we disagree about is why that aforementioned interference occurs. You describe the impediment arising from how the caster’s aura is used in casting the spell, specifically what part of the aura is used. I see the limitation derived from the flavor that the filter adds to the refined raw essence.
Both have apparent logical limitations (the greatest of which is that we are discussing magic and not science. Magic is inherently unpredictable and personal): Mine in the fact that the specifics of Mentalism’s limitations are confined to the head covering and yours in that both essence and channeling use the whole of the caster’s aura, while having similar limitations (that would seem to imply a flavor limitation). These logical limitations would appear to imply a synthesis of our opinions. I do not like that idea and now for full disclosure: I do not like your explanation for design reasons. It sounds clunky.
It's merely my opinion, but by that logic, the essence user is weaving raw essence into spells with their whole aura, their whole body. Channeling users are also using their whole body aura (they use their soul to manipulate their aura to cast.) mentalism users are only using the aura in the vicinity of their head to weave spells. (Which in my opinion is why their flows tend to be more subtle and objectively a bit weaker in physical effects.). . .metal doesn't interfere with gathering power, it interferes with weaving the raw power into spells. . . .Essence users are doing a raw power-aura-spell weave, so metal blows them the most. Channelers are doing power-soul/spirit-aura-spell weave, so metal hurts them less as they have more control. . .mentalists weaves are focused in the head, so only head metal hurts them. . .that's just my explaination, but it does fit all the game mechanics in the books as is without mods.
I have spoken to a few of my players about your idea and have tried to present the concept as positively as I could, and no one has felt comfortable with the sound of it. The mechanic, especially when synthesized with mine, congeals for them, but the sound does not resonate. I have an issue with how some of the rules for RM sound at times in other areas. If we could find a way to make our synthesis sound better to the ear, I would be more inclined to accept it.
Now for the larger issue: We seem to be attempting to explain something that maybe should stay unexplainable. Magic should be unpredictable, mysterious and personal. It should be an art and not a science. Each spell should contain the timbre of the mage casting the spell. It ought to be more akin to how a musician interprets a piece or the experience and insight that an actor brings to a role more than cold, impersonal science. Mages may talk about over arching concepts and theories as the science of sound and logic govern music, but its application must remain personal.
Well, I have a performance to get to by noon (less that two hours!).
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I definitely agree that flavor is important. Problem lies in the fact that actual mechanical explainations are campaign world specific. I'll delve my end a bit.
Core rules:
A personal Aura, or energy field associated with the body is the caster's magical tool. This is laid out both in the fact that items in contact with your body (personal gear) makes RRs at your RR, not their individual material RR. (Unless their individual material RR exceeds your personal RR.) SPELL LAW. It's also played out by the rules on intelligent item casting, the item uses your aura "Like a radio uses a transmission antenna" to cast spells, so the spells it casts count toward your 1/round casting limit. (Items capable of casting using their own aura are considered construct creatures.) SPELL LAW and CREATURES & TREASURES.
Non arcane essence has a flavor. This is laid out in the Channeling skill (SL and CL) and in how multipliers/adders work. (SL and CT)
I view the variations in how the three realms work, and how they are affected by armor/gear to be explained by both flavor, and aura use.
Opinion:
In terms of my in game mechanics, this is the nitty gritty explaination of the above. This has no bearing on other people's games, as it's a campaign specific explaination:
The aura has focal points. This personal variant is rooted in the concepts of Chakras and Kirlian auras. These points are distributed around the body and interconnected in a pattern similar to the distribution of neural paths and clusters.
The focal points of the aura are also the actual anchoring points of the soul to the body.
Channelers use all focal points as a "lens" for casting, full body use, but they are actually using their soul to activate their focal points, so they have an "otherworldly" push behnd their material efforts. They are hampered by any metal, but not as much, and ignore dead organic matter.
Mentalists only use the focal point in their head as their "lens" for casting spells. This use of only one bit of their aura explains the "head only" limits, and their ability to cast with a higher degree of subtlety. The flavor element is also there in that they are affected by metal and dead organic head cover since all efforts are made in the material realm.
Essence users use all their focal points, whole body, via control of their feel for their body. (A sort of deep mental/emtional self control.). They are affected by gear over their whole body as a result, and affected by both metal and dead organic since their method is totally self powered in the material realm.
But once you delve into enough specifics to create a logical explaination, you've entered specific world details, and that explaination likely won't apply to other campaigns. The generic answers are unsatisfying, mostly because they are generic.