I'm not calling this a "Dymaxion update", because I'm still not on Dymaxion…after 2 weeks, I'm getting close, but progress in adapting has been slow.
The long slog of low-level sleep-dep has exactly the effect I was worried it would: By the time you start reducing cores to really get down to your desired schedule, you've been fuzzy-headed for over a week already, and your willpower is a bit blinkered, as is your ability to think clearly and be creative when you need to be. It's the same problem you get with adaptations that don't work at first, and get continued and continued: One runs out of all the necessary energies, slogging through sleep-dep that long; even if it's not *bad* sleep-dep (and for the first couple days after the first big change, it is…it just gets about 50% easier after that, but sticks around).
For me personally, I'm also not doing well with the 30m naps. I think I've only gotten the entire 30m a few times; mostly I reliably sleep my 20m, and then am tired again and wanting a nap in about 4-4.5h, leaving me overtired by the time I do sleep (but apparenlty not enough to sleep 30m — maybe I need to set my alarm later, since the overtiredness DOES make me take longer to fall asleep than normal?) My adaptation-buddy is having better luck with this, though, so it might just be how used to 20m naps I am.
Still! I'm determined to keep trying, and hopeful that if I get a few more perfect days in with my 90m core and 30m naps, I'll feel better enough to adjust the core downward again. Or I could leave it where it is, and see if I can adjust to it fully enough to burn off most or all of the sleep-dep, so I have more energy to move forward? …Obviously I'm not 100% sure, but fortuntely I have an excellent buddy and a great group of people in the Slack chat to help me ponder and decide.
Wish us (long, slow) luck!