What are you referring to? Forces applied to the pedals that are resisted only by the structure of the divetrain and not transferred to the wheel? It may be difficult to measure directly, but it's all very quantifiable. And I hope it is obvious - that it not a stretch to say - that stomping or applying any downward force on a pedal that is already at the 6:00 position (or the rest of the way around until it gets past 12:00 again on a typical road bike) will get exactly zero energy to the wheel.

In other words, stomping may be effective, but stomping through the very bottom of the stroke -stomping so forcefully that one bounces up and down - is a huge waste of energy.

It seems to me that what really works best is not so much stomping as a pulsating kind of mashing.