Marty232

Why do most fit sites recommend that you knee be over the pedal axle when the crank is horizontal?

Machka 

For the same reason that your knee is supposed to be in that position for a squat or lunge, or a yoga move ... to protect your knee.

993guy

Neutral knee position?

G60

https://www.sheldonbrown.com/kops.html

roadwarrior

It's interesting...I've read that article several times. And then put hundreds of people on Spin Scan and look at their wattage and cadence go up and down depending on their position on the bike. And KOPS typically becomes the "sweet spot" when they pedal on the computer.

These guys have a lot to offer and there are always going to be varying opinions on what is best. But this article makes me chuckle in that it reminds me of a video I saw of Zinn talking about how to adjust a rear derailleur. He made it sound more complicated that flying to the moon.

Given the lack of a way to confirm your power and spin output, as well as your pedal pressure with your right and left foot (50-50 or close?), KOPS is a great way to set up your bike.