The reality is that if there was one perfect length, everyone would be using it. Teams, sponsors, and manufacturers of the industry all spend millions of dollars every year on developing technology and looking for seconds. And so far, there's still no conclusive evidence other than personal preference - that seems to *generally* correlate with rider size.

Torque only starts. Horsepower is what maintains.

You've neglected deflection of joints, ligaments, and muscles increasing.