Flying bull,
If you are in the low hover, you should not just dump the lever. Chop the throttle and cushion with remaining lever.
If you are in the high hover, then yes, dump lever AND chop throttle. Then endeavour to get forward airspeed. Unless you are very quick here, then it's curtains; irrecoverable unless you are quick.
Im with Flying Bull.
If you're sitting in a type with twist throttles on the collective, and you can react and cut all engines within 0,5s: then do it in the same time as you dump the collective.
Otherwise, dump collective as Flying bull said, or crash.
Never experienced this live, but a lot in Full Flight Sims, different types. All Sims teach the same = if you dont react quick, the rotation speed will be very high very soon.