Power all comes from the legs, then the hips and the arm just gives somewhere to go. If your not feeling that push from your rear leg with your cross then you need to drill some more
This is a good learning experience for anyone.
Honestly the hand work is nice, brings his hands back up and the shift was clean. A big problem though is that he's not pushing off that back foot for power and instead is dropping his hips and turning, which is why his foot drags