|1 person marked this as a favorite.|
Benefit: An extended spell lasts twice as long as normal.A spell with a duration of concentration, instantaneous, or permanent is not affected by this feat. An extended spell uses up a spell slot one level higher than the spell’s actual level.
I'm personally of the opinion that Feats, being options meant to add a level of customization outside of the norm for your race or class, can be "turned off" if desired. Otherwise it looks like the Devs intended for Extend Spell above to automatically apply to all spells prepped or cast as long as you have the open higher level slots and the spell is an applicable choice, (there is no "you can" or "you may" clause, you just do it). There is a "can" in the brief description, but that's obviously saying you are able to do something that others can not without this Feat, not that you have a choice.
Even some things like a Feat that grants a +1 to Natural Armor I can see, not being turned off, but rather purposefully not used by the possessor under some circumstances. They might have tougher hide (or scales or whatever), but I'm not sure that applies to every single portion of their anatomy at every single point in time, so they might want to get a piercing or tattoo in one of the lesser protected areas, and I don't think that was meant to imply that their eyeballs are also scaled (eye lids perhaps, but not their eyes or other sensitive areas).
So, in my opinion, and I don't believe that the rules really favor yes or no in a more universal sense than the other, unless the Feat specifies that it can not be "turned off" or general logic would prevent it, you can in fact choose not to utilize a given Feat, (getting neither the benefit or the drawback). It is case by case, so something like the Elongated Skull 3-in-1 Feat from Occult Adventures is something you probably can not "turn off" as it literally changes you permanently. I'd say anything that you get from "special training" should allow you to choose not to do that thing in the normal method, at least generally speaking, neither getting the pro or the con for taking the feat.