I think there is a misunderstanding about what I said.
I favor a straight arm even though other bent elbow ATP players may have a 'high level backhand' by virtue of holding their own at the top of tennis. But if one technique, I call the 'chest press', is more widely used, I can favor it, advocate it and point out why in my opinion. These techniques are evolving all the time and it really is interesting the variety that is successful out there. I can't prove what is best. But I can identify techniques in videos and speculate about the biomechanics.
It is important that if you do the same stats at your club or tennis courts, I'd expect you to find fewer straight elbows than bent elbows on 1HBHs. I see the 'chest press' with straight elbow (and other sub-motions) as the biomechanical characteristic of the best one hand backhands in the world.
Here are the one hand backhand in 2019. There are compilation 1HBH videos.
Roger Federer Leads The Way, But Dominic Thiem, Stefanos Tsitsipas Will Carry On The One-Handed Backhand
www.atptour.com
At this point, what do you think the stats might be?
Of the stronger 1HBH players I was guessing 90%+ straight elbow before you discovered Dimitrov had a bent elbow. If you find a 3rd player, I'll look over the list and see what I can find. I hope others with post.
Also, since children have been discouraged from learning the one hand backhand for many years, it is not clear that the issue - 1H vs 2H - is resolved. Single frame using the
period & comma keys.
Note - at the time, the 5 year old played tennis with a 2 hand backhand.