That would be http://lesswrong.com/lw/5n0/optimizing_sleep/44zu
As before, I'll suggest testing yourself against Gbrainy and dual n-back (as well as Anki, I suppose). I recently recovered my old polyphasic sleep logs off a backup CD I didn't know I had, and unsurprisingly, my Gbrainy scores were consistently bad; not that I ever felt I 'adapted', anyway.
On a side note, I just finished up a few months of on-and-off melatonin use, recording nights with my Zeo. I haven't updated my site yet, but the summary is: total sleep did fall by ~1 hour, REM fell by ~25 minutes, fewer awakenings, and morning feel was the same. So, I can definitely recommend Zeo for tracking things to do with sleep.
During our latest meetup, the DC Less Wrong group has decided that we are interested in experimentally testing various lifehacks on ourselves (on an opt-in volunteer basis of course).
We need two things:
Do any other groups have any measurements that they take to track their various attributes? Anything that they'd be interested in testing?