I tested it four times. Each time I failed, figured out the reasons I failed, removed those reasons the next time, and failed again. I've concluded that it doesn't work, at least for me and my friend.
I maintained a semi-uberman sleep cycle for about 2 months during college (I was Alex_Altair's polyphasic-buddy, for my second attempt). I slept for ~3 hours a day during this time. We spread it out into four 30 minute naps. The transition period took 3 weeks for me (I believe Alex_Altair did not successfully transition, and we abandoned our team effort, but I continued on my own). I would sleep through my first class each day (approximately 50 minutes) and then maintain the sleep cycle properly for the rest of the day. I eventually screwed up sleeping on ...
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.