But would you allow a noble warrior to use his spell in RM2 to buff up party?
Personally, I think the intent of the designers was to limit the spell to the Noble Warrior's own clothing/armor. You can see this not only in the fact that the spell list was later changed to only affect the Noble Warrior's armor, but also in the caveat they give at the top of the spell list in the original version in RM Companion III, which reads:
Only one spell from this list may be active on a given individual and his set of armor.But I think it was worded poorly, because literally, that would not prevent the Noble Warrior from casting the spells on the list on his party-mates. So the Rules As Written (RAW) seem here to contradict the Rules As Intended (RAI).
Does the party Noble Warrior have enough PowerPoints to cast these spells on everyone? That is one limitation the spells have in both the RAW and the RAI. Semi Spell users tend not to have so many Powerpoints.
Anyway, you have to make the call. I personally would say to my group, 'Yes, the spells literally could apply to other characters' armor, but the intent of the designers was clearly that it only apply to the Noble Warrior, so I am making a ruling that it only applies to the Noble Warrior's armor.'