I first found out about polyphasic sleeping, and the Uberman sleep scedule in perticular, through a number of (often ill informed) references in mainstream media and the press. I have a feeling that my very first exposure to the Uberman sleep schedule was through a travel article, in which the author decided to experiment with the process as a way of optimising his travel time. From memory he didn't adapt to the schedule correctly, and simply wound up completly over tired. He was by no means the only one to have this experience.
I've heard many different figures bounded about regarding the number of people who fail to adapt to the Uberman, versus the number who manage it. From looking through different reports, as well as my own experience, and after reading hundreds of blogs from those who have tried, I would surmise that the figure of 98% is about right for the failure rate in the first month.
This estimation, of course, creates a very interesting conundrum within what is quite a large and enthusiastic community. Namely that roughly 98% of the information you will read regarding the process is writen by people who were unable to adapt! And it is my sad experience that the people who did not convert, write about the process with as much conviction as those who did convert, if not more. The only way that you will be able to decern ill-informed information (blogs, websites, etc) will be because they either stop blogging abruptly (usually within the first 2-4 weeks), or they may have a small note tacked somewhere saying that they were not able to adapt. No one like to admit failure, after all.
Are these people trying to perposefully mislead you, then? I don't think so. They are passionate, and want to pass on what they have learned... and perhaps also like to act the teacher, a bit. This type of behaviour is certainly not reserved for the polyphasic community, but is especially pronounced within it. And there is a very simple reason:- this process is tough in the extreme. Only a manic desire, bordering on obsession, will see you through to full adaptation.