Not quite, you try and sleep at set times and after some time you adjust to actually sleep during those times. Since the sleep period is typically very short (~30 minutes), the idea is that your body adjusts. From what I've read, people who've tried it (for longer than a month or two, ie they actually adjusted properly) found they were just as rested as everyone else.
Having said that, who knows what negative effects it may have on them...
I've read multiple accounts of people who tried it and claimed they were just as rested. But I emphasize try because they no longer do it, and I bet the reason is they were not just as rested.
There was that guy (though I cannot remember who it was) who claimed to have sustained polyphasic sleep for 9 months and only stopped it because he found it hard to interact with people and socialise because his schedule was too different from everyone elses. But, I have no evidence, so.. that FAQ seems reasonable though.
I tried it for six weeks, but never got it to settle down into a reasonable schedule. I'd have a few days of pretty good sleep, followed by a hard crash, then a struggle to get back onto the schedule etc. Especially falling asleep quickly was very difficult for me (whereas I fall asleep very easily on a normal schedule).
From what I read, it took quite a long time. Between one and three months, depending on the person. I guess three months would be pretty painful. I've never tried it personally, so...
