Again, my point about walking on hands remains the same, it's just as much about balance as it is about strength. There are people, athletes, who have the upper body strength and arm strength to walk on their hands the length of the court but cannot do it because of a balance issue, not a strength issue. You are applying his ability to walk on his hands as an argument to solely explain his strength. I still think it's misplaced if you use it only to suggest strength.
This also goes back to what I was talking about before about "natural" athletic ability. Walking on your hands isn't something people just do, wake up one morning, and just start walking on their hands. People practice it before being adept at doing it. You give an athlete enough time to practice walking on their hands, most good athletes would be able to do it. There is absolutely a measure of strength in walking on your hands. But, it's also about practice and balance.