There is just so little guidance on the power, and it is easy to either take that bit as a rule, or go straight for that "focusing on" as a means to justify anything else.
As justification for what I think you're targeting, I actually prefer the reason you seem to have mentioned only in passing - some skills simply need to be learned. It does add some limits on how you use those skills with NPCs but it's good flavor, adds an interesting fact to your world, and makes sense when applied consistently.
This is a valid way to read things, but it's not the only valid way. The rulebook does not specify what happens.
Personally, I think it makes more sense for the items to stick around after the slots are lost. The items exist, and they only need maintenance occasionally.
Hmm, not sure I agree. The book is fairly clear on items & foci taking up one or more slots. If you don't have said item slots, how can you have working items? It does create a small conundrum within the narrative context...which is solved by the "must be learned" caveat devonapple brought up. Even if you don't apply that to evocation / thaumaturgy as a whole, I'm very tempted to apply it to item creation.
If I was wearing Harry's duster when he died, would it suddenly become normal fabric?
On the other hand, your interpretation mitigates the broken-ness of Modular spellcasting.
Depends what made the fabric 'abnormal' to start with - was is a change to the material or simply an oft repeated mental exercise using the item as focus? Even if it was a change to the material, do you know how to use it? I kind of agree with your next statement - there's no canon answer. But it is answerable...and either answer is justifiable.
As for what powers Modular Abilities can grant, it's almost certainly deliberately ambiguous. Standard DFRPG canon-writing procedure, it seems.
Yep. Some days I like that, some days I don't. Guess I'm almost as ambiguous...
