One of our members tried polyphasic sleep and quit it after 5 days when he realized that he could no longer adequately understand physics papers.
This highlights one thing that many polyphasic experiments get wrong. As far as I know (and I should know, having tried repeatedly to get through adaptation for 6 months, then stopped when I got bad flu) polyphasic makes everybody very sleep-deprived for the first week, and usually also for the second week. Only after that do you start getting used to it. It will take even longer to adapt the more you break the polyphasic routine.
Not that I’m recommending polyphasic. Humans have been fine-tuned by evolution for biphasic and monophasic.