According to page 69 of BWG on Epiphanies, “To shift to the next lighter shade, a player must spend a total of 3 deeds points, 10 persona points and 20 fate points.”
Some abilities—Steel, Dwarven Crafting Skills, Elven Songs, etc.—are naturally open-ended and so never need fate points to be spent on them.
My question then is this: does the player have to “waste” 20 fate points on these naturally open-ended abilities OR does the fate point requirement for these abilities get waived when shade shifting?
A fate point may be spent to reroll a single failed die in naturally open-ended rolls (p. 66). In my experience, this is in fact the main benefit of naturally open-ended abilities; fate points tend to accumulate to the point where I don’t think I’ve ever forgone exploding sixes because I couldn’t afford to spend the fate, whereas rerolling a failed die can make the difference between passing a test and failing by one.
You might get to effectively add another die by opening a closed skill with Fate, but you almost definitely get to add a die by rerolling a failure on an open skill. That’s huge! It makes Fate pretty much as strong as Persona, although you can’t spend as much.