Three Pieces at one time

Writers, how often does this happen to you: You start out sitting with one thing. Dumping out so much and in the midst of writing one book, you receive a download of another book? So you pause for a short period of time on the first work to jot down what you're receiving for the second work. Get a good rhythm going on the second work and Uh Oh! Another download...for a third work? Does this happen to anyone else? If so, HOW do you work all of these pieces at the same time or do you just focus in on one piece to complete it? See, the latter may be the smartest thing to do (don't hold me to that statement), but I always feel like if I do that, I'll 'forget' the information I've been given on the other works? OH THE DILEMMA!!! Help! Somebody help! I sure hope you didn't think 'I' had the answers to these questions? Nope, I don't! This is why I'm soliciting YOU! xoxo