As I said in another one of my comments, sleep deprivation, in my opinion, isn't actually the key part of polyphasic sleep. You can sleep 6 or 7 hours polyphasically, too, and this will increase your productivity and creativity than sleeping the same amount monophasically.
Sleeping biphasically for 7 hours or so works because that's what humans are wired for. Maybe taking two or three naps instead of one is better than taking none at all, but without the sleep dep you might as well just go biphasic. The main selling point of polyphasic is the sleep dep.
Indeed... in a short period of time where you must do X, polyphasic makes a hell of a lot of sense. As a long term strategy, I can't believe it's healthy. I'd rather not meddle with the default operation of a complex system I don't really understand, so usually I sleep until I feel like waking up - there are very few leisure activities that I'd rather do than be consistently well rested.
