Personally i like the FILD method even though its just a moderation of the DEILD method. I enjoy using this method because you don't have to train yourself to not move when you wake up, and you don't experience sleep paralysis because your not concentration on your body. To answer your question, yes, all the finger movement functions as is just an actor. It serves as a focus point to transition into a dream easier. And yes, you can attempt this after a WBTB. The most ideal time to use the FILD method is during nighttime hours, but close to morning time for more REM sleep. Good luck!