Originally Posted by elcruxio

I have pretty large feet. The difference between 45 degrees and 20 degrees is quite a few centimeters. The 109% formula puts my seat around 6 centimeters too high. It's actually three centimeters higher that the Lemond method which is also too high.

Also using the measurements is just trigonometry. There's nothing mystical about it. I could have used made up values or just split the inseam value in two and the results would have been similar.