There is definitly something to a rest period from...anything! Work hard on something for a while, then take a vacation, like, don't even look at it, and try not to think about it. Then, when you come back (and the longer breaks work best for me) there's something else there in your mind that adds to what you already knew. It's like it came from out of the blue. I've been away from my mandolin so long that David Grisman better look out! Har :-))