In reference to the hand motion after release of the ball. This is an example of what the hand will do when the arm and hand become relaxed after release of the ball. Different pitchers may have slightly different motions, but if you looked at several good pitchers with similar slow motion photography, I think you will see similar action. The after release motion doesn't do anything to the ball, but it indicates that the pitcher is protecting their arm by keeping the shoulder, arm, and hand loose. Doug Gillis has always taught a relaxed motion after release of the ball. Pitchers who force their arms to finish in a particular manner such as high above their shoulders may develop arm problems.