Ati: Yes, I would say it's almost certain that polyphasic sleep, especially with the limited knowledge we have now, is not for everyone and not for every situation. For my part, judging by the difficulty I've had adjusting even to biphasic, I'd say I've messed with my sleep schedule enough that polyphasic is not in the near future for me--maybe I'll give it another try after I've had a few months without sleepwalking
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