Ran a 12-week n=1 on myself while the trial results I wanted never showed up, and the surprise was that my wearable's readiness score and my actual recovery went in opposite directions for five straight weeks — score climbing while my knee got stiffer on the first flight of stairs every morning. Turns out I'd traded my after-dinner walks for extra sleep, and the stiffness only ever responded to easy daily movement, not to anything I was adding on top.
So I dropped the score and went to three plain columns in a notes app: date, hours slept, and a 1-5 "how did the stairs feel" number, plus a waist measurement every Sunday before coffee. Baseline was a 3-4 most mornings; by week 9 it was sitting at 1-2 and my waist was down about an inch and a half, which I'd honestly credit to getting back to 20 minutes of walking after dinner before I'd credit anything I was stacking.
Contrarian take: trials going dark isn't a gap that Reddit threads fill, it's a reason to shrink your own variables — I stopped adding things and started changing one at a time, and the boring one won.