Based on comments on this question. If the moving cam on a Gri-Gri is prevented from engaging (perhaps by a belayer firmly holding onto the device), can you still brake effectively?
By "brake effectively", I mean:
- use the traditional brake position with your right hand pulling down on the rope
- arrest a lead fall of a few meters by an average sized climber on dynamic rope, with a comfortable margin of safety
- not just by letting the cam re-engage