The first week is a $#%^$#^@$%@@#$% pain. The trick is to train yourself to fall asleep quickly (5-10 min). This takes tinkering (link below). Now, especially if I'm in one of my three comfort places (bed, couch, or car), I know can fall asleep in 5 minutes or so.
Another key is DON'T try to sleep for more than 30 minutes. The deeper you fall asleep, the harder it is to get up. If I snooze my alarm even once for 10 minutes, I'm probably going to be too asleep to bother getting up when that 10 minutes is over.
The good news is that my experience (Steve Pavlina echoes this) is that once you train your body to work on the schedule, then even if you revert to a normal schedule, you can switch back to polyphasic sleep without having to go through the painful first week again. Right now I sleep polyphasic 5-6 days a week and have 1-2 days a week where circumstances prevent me from napping during the day and I then take a full night's sleep at night. Interestingly, I feel terrible after the full night sleep but pretty darn alert during polyphasic sleep.
Agree with everything you said. I also think its easier to "ease" into the schedule. Keep a few hours of core sleep at night and still take your 30min naps every 4hrs until you feel like you're starting to get on the schedule. Then shrink and eventually eliminate the block of core sleep and you're there. Its never perfect, but at least it helps with the brutal agony of the adaptation period.
The biggest benefit of polyphasic is not squeezing every possible minute of awake time. Its the improved concentration and mood. If you want to leave 3-4hrs of core sleep at night thats perfectly fine.
I did it too. 3 or 4 days (can't remember). I couldn't fall asleep fast enough so I didn't sleep at all. Wasn't tired at all the last day but I stopped because I couldn't sleep. The result was some memory loss.
Don't recommend it.