Let me get this straight -- pushing down on the pedal is useful effort, but pulling up, pushing forward and pulling back on the pedal are wasted effort? How did you come up with that? Using the same logic, you could argue that pushing down is wasted effort, and we should all just give up riding.

Effort is "wasted" if it isn't translating into the action you desire. Here, pulling up, etc. are translating directly into rotation of the rear wheel, which is pretty much what I look for. You?