Originally Posted by TheLambsheadrep
"If ulnar deviation reaches the minimum of β and this angle is zero, due to pronation they could have very high probability to frame the ball. Thus, they should keep this angle away from zero,".
Letís compare Verdasco flat FH with Fish WW FH.
Verdasco uses wrist ulnar deviation extremely hard and gets max ballís speed. The beta is near to zero. If he pronates, the racquet long axis draws a cone with sharp angle beta at vertex. Because beta is very small it would be very difficult to catch the ball. The efficiency of spin production would be almost zero. Thatís why Verdasco, around contact, shouldnít employ arm pronation to minimize framing.
Fish practically doesnít use wrist ulnar deviation. Beta angle is near to 90į. The racquet long axis draws the disk and he can easily catch the ball. The efficiency of spin creation is max, but he loses a lot of ballís speed.