Everyman 4 Sleep ScheduleIf you have not read the Everyman Sleep page yet, then you should go read that first.
The Everyman 4 schedule is just the Everyman sleep schedule with a longer core sleep. The traditional Everyman schedule has 3 naps and a 3 hour core sleep. The Everyman 4 sleep schedule has only 2 naps and a longer ~4.5 hour core sleep. It was originally refered to as the Everyman 4.5 schedule, but most people shorten the name to just Everyman 4 Sleep.
Interestingly, though, for each individual the core sleep should be adapted to be the right amount of sleep for them, given that they take the 2 naps perscribed. This means that someone might actually take a 5 hour core sleep on an Everyman 4 schedule, even though the 4 is to indicate how long the core sleep is (this is exactly what I do; funny isn't it). The real difference between Everyman sleep and Everyman 4 sleep is that in Everyman 4 sleep, one of the naps is cut out. I say one of the naps is "cut out" because that is indeed how most people on this sleep schedule position their naps throughout the day: as if they were going to be having 3 naps for Everyman but then just not taking one of them. This is in starck contrast to the other schedules which all recommend having the nap times equally spaced throughout the day. For Everyman 4, it would not be a problem to position them evenly throughout the day, but most people don't. This demonstrates the additional flexibility of this schedule over other polyphasic schedules. The longer the core sleep, the more flexible the nap times.
This is the schedule that I have been on now for a while and almost the majority of my polyphasic time. I find this schedule to be the least intrusive. The one complaint my wife has about polyphasic sleep (and no doubt other people and their spouses have the same complaint) is that it is so rigid, i.e. it is highly neccessary that you take your naps at very close to the perscribed time. It is my hypothesis that this is the reason that most humans sleep monophasicly: it is a little more flexible to their schedule (and also does not interrupt their daytime activities at all). With the Everyman 4 schedule, what I have often done is still schedule 3 nap times, similar to the traditional Everyman schedule, but then I only take two of them each day. I try to take the first two, but if for some reason I cannot take one of them: either I am interrupted, cannot get to sleep, or the schedule of my life just gets in the way, then I take the nap scheduled at the 3rd time slot. This has worked pretty well for me. Personally, I then take a roughly 5 hour core sleep at night. I have found empirically that 5+ hours of core sleep works far better for me than the 4.5 hours perscribed. But then, I also used to sleep 8.5 to 9 hours when I was monophasic (and often still feel tired). So, I rationalize that the extra time needed in the Everyman 4 sleep schedule is consistent with my needing more sleep in general. Some people I have talked to have said things along the lines of "If you are still taking a 5 hour core sleep at night with the Everyman 4 schedule, then why take naps at all. You could just avoid the whole hassle of naps all together and only sleep a few more hours at night." This is indeed true. And, for some people, perhaps, it makes sense, but not to me. To me, I compare time to money, as they are both resources I have. In my mind it is similar to saying, "I would rather make a single payment of $9 than 3 payments totaling ~$6.5 just to avoid the complexity and inconveninece of having to make 3 payments each day." To some, maybe that is indeed how they feel, but to me, this makes no sense at all. Notice, I indicated that it was about 6 and a half dollars (or hours) of sleep in the Everyman 4 sleep schedule. This is due to the time that is "wasted" for each nap in order to get somewhere to take a nap and actually get to sleep. For me, it is actually closer to 7 because it is a long way out to my car for my lunch nap. To me, a 2 hour savings each day is still worth it. I should note, that I also, usually (unless I miss a nap), feel more rested on the Everyman 4 sleep schedule than any other schedule, including a monophasic schedule. The reason for this might partially be that I really don't have time in my life, with everything else that I do, for the 9 hours of sleep a night that my body requires, but I can find time for the 2 naps and the 5 hour core sleep.