So you obviously have never used clip in bike pedals before. Why are you trying to argue this point if you know nothing about what you're talking about?
If you're clipped in, why would you keep feet from sliding?
Preventing sliding by pushing is how effort is wasted and is a possible explanation why a cyclist might feel much stronger when clipped in and no longer has to push - while attributing the lower effort to the upstroke pull.
Preventing sliding by pushing is how effort is wasted and is a possible explanation why a cyclist might feel much stronger when clipped in and no longer has to push - while attributing the lower effort to the upstroke pull.