Original Message

The switch in question is to test the overrun shut-off. It’s system check once a day. The overrun system basically will cause an engine shut down if RPM becomes dangerous.
The 600N basically operates at 600shp. In manual mode or runaway it can go wide open to 800+shp which can start removing blades.
MD decided that a forced shut down and auto with blades was better than no blades.
I’ve never heard of it happening and in manual mode the pilot CAN control the shp to the drive train but you’d better be fast and smooth