FWIW, here’s my N=1 experiment.
I wanted to see how many watts I could produce in a max sprint one day (disclaimer: I don’t even have a sprint, and for the most part, I don’t care to), so at several convenient uphill locations on my commute home, I gave ‘er hell (slight heck, actually). I got home and looked at the numbers, and the next day, I tried again. Thinking I had been in too tall a gear before, I tried a lower gear this time and got a roughly similar result. Curious, for the next few weeks, I kept trying (when I felt fresh enough), futzing with different gears and cadences each time. The result: between 70 and 110 (ish), my max power was broadly similar (I wasn’t concerned with how long I held the power, just the biggest number that appeared on my Wahoo).
I had been hoping that if only I found the perfect gear, I’d find 200 extra watts hiding in my legs. Alas, those watts are still hiding.
On the complete other end of the spectrum, shortly after taking up cycling, I was on a climb, and a steep pitch sucked my wind, so as the gradient eased, I dumped it into the 32 and tried to recover. But I didn’t. I was in my lowest gear, for gosh’s sake, and it wasn’t getting easier! My legs kept hurting, and my hr and breathing weren’t slowing! Spin it to win it, right?!?!
It occurred to me that maybe an upshift would help? I clicked up one, then two, and holy cow, it felt better, and my breath was coming back (speed constant, cadence decreased). So instead of my little legs flopping around at 100, they were spinning nicely around 80, and so much for spinning it all the time, regardless.
As much as I’d like the idea of one Cinderella-slipper cadence, it seems that we meatbags have different muscle types and metabolic pathways that mix and blend and do different things at different times, and depending on alotta things, the “right” cadence can be alotta different numbers.