I saw a show about dreams a few months ago on P.B.S. They said that new research suggests that during sleep the brain works on problems. The tests ran from humans learning to play a new video game, to rats working on a maze.
So, if you try to interpret dreams, couldn't you end up in a circular situation, in which you end up dreaming in order to solve the dream you are trying to interpret?
I tried this once. I kept a log of my dreams and tried to apply (I think it was Cayce's) an interpretation to it. My dreams just got crazier and crazier.
Pay more attention to anything and it will take up more of your time.