All I can say, "upside-down tree", is the further back you go, the more usage the 'power/speed-select (for main rotor rpm)/'throttles', got.
On a modern helicopter, such as the EC225 LP, the engine control switches have 3 positions - Off/Idle/Flight, speed of the main rotor is controlled completely by the FADEC, dependent on collective position, no manual reversion as per the AS332,mentioned elsewhere.
I also think TC had been on the hooch before posting!