[markandrewj]

I used to think like this, but it isn't true. After riding flats, rat traps, and clipless, I can say with confidence that clipless peddles are more efficient when climbing hills. I don't think it is as much about providing power on the bottom as it is about being able to pull up while going through the top. It especially makes it easier to keep a consistent tension while doing long uphill climbs. Rat traps work too, but I found they would catch on things constantly. That said, I use a pedal which is clipless on one side, and flat on the other. Depending on the situation I might use one side or the other (i.e. I might switch to my flats if I am riding in a busy downtown area where I might have to stop unexpectedly). Good technique will of course help you whether you are using clipless or flats.