Ascend Charlie, if they flip the rotor to the other side one or the other then surely there is still going to be one blade moving up into the down-wash in either case so why does it matter?
With the tail rotor is aft of the disc, is the down-wash going to catch that much of the tail rotor anyway?
What about the effect of the vertical stabiliser on the efficiency of the tail rotor? Is it better to be blowing air onto the stab or sucking air around it? Does it matter if the vortices generated by airflow past the stabiliser are being drawn into the blades or being created on the outside of the stabiliser?