My experience is the opposite. It is only because I can get free of the clutter that I can actually do creative work. I do often have to schedule it and it does often require several hours at a time. I believe that there is such a thing as a muse, but also that very few serious artists sit around and wait for it to appear. They probably coax the muse into the room by adhering to a rigorous schedule and by setting up frequent work sessions. Just my guess.
Winning Proposals With Style