Originally Posted by Anton
Its timing impact - if you are late for the shot you'll probably hit with bent arm, if you are early you'll meet the ball more in front on a straight arm.
Here is some of my stroking from 3 years ago:
When that ball is coming in quick and high I have to bend my arm in to hit it late.
very nice. great strokes.
now that's the way to use the wall. excellent work.