Helicopter pitch change when orbiting around a fixed point??

[Three Blades]

We have had this discussion before but I still find it interesting.
When I look at it from a Newtonian mechanics point of view I see that there is little argument for power change (as per the first post). However there are plenty of pilots with many more hours than myself who state that this is not the case.

As such I have this question:
If you execute the turn with a lot of pedal input, does this mean that the helicopter rotates within the airflow without accelerating through the circular turn and hence will require power for the downwind leg ? The alternative of a 'pedal free' turn means that (in theory) the helicopter accelerates around the turn and hence maintains the same IAS.

I have trouble with the accelerating mass theory relative to the Earth as mass is not related to gravity and this acceleration would still be required in space.

Clearly we have to assume flight OGE in all cases here as otherwise there is obviously a GS factor to be taken into account.
Also we cannot assume that you start from S&L flight but are in a constant turn as you will clearly need to raise power to initiate the turn.

I am looking forward to hearing the universally accepted argument to this one.

TB
(low time, engineering trained, pilot)