It seems (for me) that actually there's no need to limit the 50-level-graded powers, which have been defined as "spells" or "spell lists" for years, into those from magical power sources.
Yes, as you might expect, this thought comes into my mind so smoothly as the most recent official incarnation of the progenitor RPG eliminated the magic-users' monopoly over the immense volumes of specific individual powers. They are now on the way to expand the powers from traditional magical realms like Arcane and Divine, or if using RM terms, of Essence and of Channeling, into broader variety of realms like those including Martial (of Arms, if using RM terms), Primal etc.
Today, I found that some of the Beast Master profession's "Spell" Lists such as Combat and Movement Enhancement being more physical or instinctive or maybe intuitive sort of powers rather than magical, and that made me wish to avoid using the term "spell(s)" for those lists.
By chance or maybe by some subconscious (maybe not), IMHO, Rolemaster systems recognize or express those individual exploitative resources as "Powers" like in "Realms of Power," "Power Points," etc, (though they have been strictly limited to magical realms). I guess these will be able to provide a good momentum to expand the "Spell Lists" of magical realms into "Power Lists" of various realms. And if such momentum exists, I would call it "trend of the time" or maybe "(r)evolutional process" rather than "opportunism" or "imitation."
Just my two "yen"
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