My interpretation of the efficiency of the Equalizer cam: As with most cams, the weight builds as you draw. The E cams are near peak at the front. Other cams will hit hard, initially, at release. Then deliver less energy as the cam rotates toward brace. The E cam will not hit quite as hard initially, but will continue to deliver more energy, as it returns to brace. If I'm right, this would account for the higher efficiency with heavier arrows. Possibly with shorter draw lengths as well.