I almost mentioned A,B and C in my first post but decided not to complicate the explanation for denlopviper.
A.agincourt - I am afraid it is you who are not quite right old boy - Factor A is the disc tilt which does reduce the inflow angle - so does factor B which is the increase in the horizontal airflow BUT!!!! Factor C saves the day as the air is effectively moving faster up into the disc compared to the air that was being slowed by the disc. Factor C is essentially an increase in RoD flow which increases the inflow angle again. Therefore no loss of autorotative force and no reduction in Nr.
Graviman - flare effect is gained by changing the angle of the induced flow into the disc, reducing its magnitude and thereby generating an increase in AoA and rotor thrust. At zero speed in auto, all the RoD flow is coming straight up at the rotor and any cyclic change will reduce the RoD flow and reduce rotor thrust, thereby increasing the RoD itself - not what you want to do for an EOL. Read fewer textbooks and go flying more
