Is fixed bad for your knees if you dont skid / ride high gear?

I reckon the whole "fixed sorted my knees out" stuff we always hear is probably down to the fact that the constant pedaling action forces some amount of warm up and cool down, and rounds out the pedal stroke to a certain extent. Certainly some of the outlandish bike positions I see on the roads would contribute to no end of problems.

+1

Some of the bad habits people have when riding geared. Are not possible riding fixed. But if you have half decent technique, 'its all just riding a bike'.