Is his head swaying to much in the backstroke (and staying too much back on the downstroke) - or is it "perfect"? He's not following the ball with his eyes and swivelling head to any degree it seems..
His head is so far from center, it should have its own Zip Code.
I don't understand the Drill but I have a hard time finding value with it. I can imagine the problems it's causing but maybe someone else has used it to effectively learn something and I'm missing the point.
As with many drills, there are often benefits, and drawbacks.
The benefit of this drill (with the ball) is that it helps ensure the pivot moves, and also helps maintain rhythm - certainly better than most people have anyway.
the drawback is that it encourages the breakdown of the right arm flying wedge and level right wrist.
In short, great for pivot work without a ball (zone 1)
not good for hitting shots unless you are aware and monitor the right forearm and level/bent right wrist (it breaks down zone 2 and zone 3 alignments, 3 more than 2)
It is better than putting anything under the armpits though
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