When people tell someone to "sleep on it" they are usually trying to say "think it over, make your decision tomorrow." But when someone asks you to "sleep on it" and they really want you to put something under your head and fall asleep, what do they mean? I'm not sure what significance that would have on anything. I slept on my class book, and had some crazy bad dreams, but I feel no closer to an answer. I guess my guess would be that there is no point, but thats ok. You don't have to do everything because there is a reason, not everything has to be deep.