[Basic] [Magic] Using DFRPG spell descriptions to clarify GURPS ones

[johndallman]

The Infinite Cabal party want to do spectroscopic analysis of auras, because some of theirs are changing in interesting ways, and they'd like to measure this objectively:

Originally Posted by Aura spell, GURPS Magic p. 101

Creates a glowing halo, or “aura,” around the subject. This aura gives the caster a general insight into the subject’s personality . . .

It isn't clear if that aura is generally visible, or only to the caster. By contrast:

Originally Posted by Aura spell, DFRPG Spells, p. 42

Lets you see a glowing halo that reveals whether the subject has Magic Resistance or a spellcasting talent, and at what level . . .

That version is quite clear, and makes a Visible Aura spell necessary.

I'm happy with that decision, but I'd like to ask if DFRPG Spells is intended to be usable in general to clarify spells that it covers?