Flt tests
The test mentioned was for looking at extended range performance in a light teetering rotor system - not really for this discussion. No argument aft cyclic will increase NR if you have airspeed and if you have lowered collective.
Don't confuse positive G with aerodynamics, all positive G means in an auto is you are slowing by flaring either in pitch or during a descending turn. There is no level flight in an auto. The flare is increasing NR by increasing the angle of attack of the relative airflow to the rotor system.
An Auto by definition means the helo is descending and the relative air flow to the rotor system is from below, angle dependent on airspeed, no requirement for aft cyclic other than to control nose tuck. Just tested it at a variety of airspeeds in a large helicopter.
If you induce aft cyclic at low IAS you just made the situation much worse as you have bled off Airspeed and as indicated by the study where they mention recovering entry auto rpm by lowering collective. Now your in the worse of both worlds, no airspeed and low Nr.
Don't confuse technique to get a smooth entry during routine practise with what will happen when your caught by surprise and NR is already 90%.
To answer PG , NR will recover by doing nothing more than lowering collective aft cyclic is not required to regain NR, it does control nose tuck, done it numerous times, even waiting for the 2 sec count and doing nothing else. In fact it is better in a helo with stabilization not to touch anything except the collective, stabilizes in the auto much quicker., yes you need to re reference the IAS.
please discuss with training staff, this is a complicated discussion and varies by type there is no one answer that fits all and cannot be properly discussed in this forum