Yes, something odd happened and you will never know cause you don't want to listen to one of the few men have studied this in depth for years, as he explains it to you. Because of Querry's western grip (and probably a lower contact closer to the frame), the same amount of torque will a allow the face to cover the ball quicker than Fed's more moderate grip. Even with Fed's more classic grip, he almost covers the ball in the same manner as depicted. Fed's swing just has more lift in it, which provides more vertical separation from the ball. Q's swing was flatter. Nice catch teachestennis.