Paul Cantrell
As I mentioned, Prouty claims that at zero airspeed in autorotation you are actually in Ring Vortex State which says recirculation is taking place...
My copy of Prouty doesn't say that, he highlights the difference between VRS (power applied with moderate RoD), and windmill brake state where all the flow is from beneath the disc and the rotor is extracting the energy to keep turning from that flow. Will there be recirculation at the tips - yes but it doesn't mean you are inducing a flow top to bottom with power.
You may well be correct that the R22 has a different drag curve to other helos with higher disc loading.
There is no doubt that the RoD in a zero speed auto is higher than at bucket speed - the only element for discussion is how much. In every helo I have flown (with widely differing disc loadings and AUMs) the RoD at bucket speed is between 1800 and 2500 f/min and the zero speed RoD doesn't vary by more than 500 f/min from that figure when in steady state.
I mentioned fuel flow graphs only because of the identical shape on the ones I have seen to the power required curve - since the power required curve is exactly what it says, then in powered flight the engines(s) are always providing driving force (if only to overcome rotor profile drag).