My recall so far from Lucid dreams is close to 100%, as in i can play it back as if it was a video in my head. I can compose entire songs in my head while awake, but i think the advantage of doing it while lucid would be that you could make it appear visually, so it would be easier to write down. I'm going to give this a try the next time i become lucid, ill post back here if it works.