whenever i go with such little sleep (as i often do) i find it very very difficult to get lucid or even dreams at all...dream recall is horribly hindered by sleep deprevation...on the other hand oversleeping (as has been stated) = dreams++++ ...its about dream recall really though, and not lucidity...i couldnt help with the lucidity part...problem with the sleep deprevation is the only way you can wake yourself is more sudden or 'violently' and in the course, you forget your dreams, while oversleeping, your mind skims the edge of reality, forcing itself to dive back into the dream world but occasionally reemerging to the physical world, and phasing back out again...kinda a slow progression wake up thing that helps with recall etc.