With all due respect to rtc I have some knee movement when I pedal. I also have some classic chlondro-whatever symptoms, but not serious enough to worry about it. Trust me, I worried about it for a long time when I had first started riding, especially since I read about John Howard and his knee problems (magazines seemed to be writing articles on him and his knees every month). But ultimately I seem to have avoided problems. Just like my training in general, I never did anything specific. I just went easy when I thought I should (pain etc), harder when I felt I could.
cdr