I haven't read the whole guide yet but on page 8 it mentions polyphasic sleep (with annotation that majority of people who try it fail). Isn't polyphasic considered a popular hoax? As far as I remember, mentioned in the presentation dr Wozniak actually believes it simply doesn't work. Also, I've read a few blogs of people who tried it and failed (some of them appeared on HN) and don't recall a single person that succeeded. Taking that into consideration it makes me feel sceptical towards this guide. Sure - some sleep patterns work for certain people and don't for other, but why include something that seems to work for noone?
I was polyphasic for about six months a number of years ago. My schedule was a fairly standard 6x20 minute naps (commonly called the Uberman schedule). After the initial (very, very difficult) adaptation period, I felt great nearly all of the time. I would get tired right before a nap, but by the end I didn't need an alarm to wake up after 20 minutes, and naps left me feeling completely refreshed and alert. I was in graduate school at the time, so my schedule was pretty flexible, and I had a mixture of cognitively demanding work (my research: a project in geophysical fluid dynamics) and less mentally demanding work (grading, family and home responsibilities). Again, after the adaptation period, I wasn't particularly cognitively impaired.
There is a lot of misinformation out on the web about polyphasic sleep, both by its proponents as well as its detractors. Some of the things that have been written (polyphasic sleepers only get REM, for example) are just false. One problem is that there isn't a very large body of peer reviewed literature on the subject; the canonical reference is a volume of conference proceedings from 1991 which can be hard to lay hands on. The fact that (a) adaptation takes a long time (on the order of weeks) and (b) the polyphasic schedule is incompatible with the way most people live their lives has made researching it difficult.
I'm currently involved in a polyphasic sleep experiment organized by the folks at Zeo. They asked for some volunteers to use their hardware to monitor our sleep as we either adapt to a polyphasic schedule or (for those already adapted) function on one. We're not following any kind of rigorous experimental protocol, so this isn't going to be publishable research, but it will at least provide us with some measured anecdotes.
People who say they managed to pull it off for a month or two keep popping up. They could be just pulling our leg of course. When I suspected the people who say they've successfully done polyphasic sleep are just making up stories aloud in IRC, someone on the channel told me they'd done polyphasic sleep for several weeks.
I'd consider polyphasic sleep as working if after within two weeks of starting the schedule a significant number of people could start going instantly into REM sleep when they nap and could stay reasonably alert and functional with these naps for several weeks. This should be easy enough to test in a lab.
My guesses are that it can really work (but I'm not sure if it can work for most or for not that many people) and that it's likely to impair mental performance a bit even after successful adaptation. I haven't read many polyphasic sleep accounts from people involved in seriously brainpower and creativity intensive work like mathematics research. Also, I'm a bit wary of cutting away non-REM sleep, since it seems to be the time when the body heals best. I keep thinking that the body might be using the NREM sleep to clean out cells turning into cancer in addition to healing wounds and fighting sickness, which would make long-term NREM deprivation life-expectancy shortening.
It's not so much that it doesn't work, but that it's at extreme odds with the rest of society. I can't say much for the Uberman, having tried it three times so far and failing each time, but I did do the Everyman for a period of a couple months with no ill effects. I tried again a while ago but I just can't keep it up when school is going (which was my reason for stopping before).
I'm not going to go dig up some research (though the PDF seems to agree we're at least biphasic) so you're free to take this as opinion, but I'm sure I've read some out there suggesting that humans are naturally polyphasic and evolved that way in the ancestral environment. A just-so story could be that those who slept less or in bursts avoided deadly danger better than those who got 8 solid hours each night.
All the accounts I have read seem to think it worked but go in the way of their lives to much. I doubt there are many out there which would be able to test this for a long period of time without anything at all getting in the way. From the sounds of it missing a single nap was extremely taxing.
