Hi, I loved your explanations and after listening to that I would love to read your point of view on 2 hours of sleep 4 times per day ("sommeil polyphasique" in French), is it possible to have one cycle on each of the 2 hours?
Since sleep cycles are usually (but not always) 90 minutes, sleeping in 2-hour chunks doesn't make a lot of sense. :) If you want to sleep polyphasically, go for 90-minute or 3-hour chunks instead. It's not something to just play with casually, though -- sleep deprivation can give you actual brain damage. My upcoming series on polyphasic sleep will give more info.
Mano