I find all this talk fascinating. If you ride and do't see the benefit to clips or clipless pedals do not use them. Most so called studies in cycling seem flawed. My experience for the last 35 years of riding is that I cannot effectively apply power without tight foot restraint. This does not come into play when casually riding on flat terrain. If I need to climb any kind of grade I need to pull up. Also pulling up comes into play for high speed and or long distance riding. My practice is to ride high gears with low RPM's where I can more effectively apply force around the pedal circle. I find it hard to pull up when spinning. The forces of high gear low RPM pedaling are higher but this is mitigated by sharing the forces with both legs the pushing and pulling legs. I have less knee problems when I ride higher gears because my leg strength is higher and more balanced between the front and back of the leg muscles. I find much cycling science so fascinating, try higher gears but never change things suddenly, you have to condition the body to use higher gears gradually. I AM NOT ADVOCATING ANYTHING. I just do not believe in doing something because some expert says that that is the correct way to do it, the fads come and go and everybodies body is different.. Brian Blum in Berkeley