Originally Posted by
FlashBazbo
Misaligned cleats are a different issue. The misalignment imparts a torque on the joints up the leg in a 1:1 ratio.
On the other hand, a properly aligned cleat that is 1mm out of place causes the joints to be very slightly more bent or less bent (but still in the proper plane). And because of the distance involved, a 1mm change at the foot translates to thousandths of a mm at the knee and hip.
When I went from 175mm to 170mm cranks on my fixed gear, my leverage on steeper hills was perceptively out of whack. I also could spin about 5rpms faster without my thunder thighs flailing around and bouncing me off the saddle. Same tires everything else. I adjusted, but it took a week or two.
Your 'thousands of an inch' sounds rational, but when it all comes down to it, it changes the torque you can apply, and that's what people feel. I bet the ratio is fairly significant, considering I know weightlifters who can feel if one foot is 1cm off parallel with the squat rack.