Originally Posted by Ash_Smith
Loving this discussion!
My "issue" such as it is with the "working across prior to contact" as an instruction is that if you look at Toly's image, whilst you can see that Rafa's hand is moving across his body in those frames (it has too because it is attached to his arm!), it still maintains the same distance from his body throughout. With an instruction of "working across prior to contact" there is a big danger (imo) of players literally pulling the hand across and therefore closing the distance and likely causing the elbow to rotate out and consequently losing stability.
The picture below absolutely clearly shows that there is no special horizontal “across aspect” due to the racquet tip constantly moves to the left. Thus, it can create clockwise sidespin or no sidespin at all. But, according to Wegner there should be significant counterclockwise sidespin.