ankling at high effort is a very easy way to get tendonitis in your achilles the likes of which you wouldnt believe

my feet hold about the same angle in relation to the ground the whole way around, and its slightly toes down

calf muscles are only supposed to keep your foot in about the same angle in relation to your lower leg, not directly contribute to putting power to the cranks, if your letting your ankles move alot all your doing is decreasing the power to the cranks a bit....think about it, crank comes around back to the upstroke, you let your heel go up, that brief movement alone during that transition is a few degrees your NOT applying full power on the upstroke