Some of us have wondered about this....
Start with a rock-solid right arm, upper body steadiness including engaged lats, and an instant brain-body connection, because instant response is important in technique, and technique is key (it's not about arm length). A grip higher up on your opponent's hand is better. Grip is critical, as much through fingers as through wrist. Your main move is to pull the opponent's forearm away from his chest, and the higher your grip, the more leverage and power you have. Quick response is very important, hence the brain-muscle connection and technique.
Grip strength especially through finger spread, not just wrist level grip. Practice with others of similar strength for technique and speed of response. Develop integrated chest-shoulder-back arm strength and stability, and also fast power and response.
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