To avoid hitting the shanked shot off of the heel, we want to concentrate on your arms and the club not coming out so much, but more vertically in towards you. Bringing your hands — and therefore your clubhead — in towards your body is taking the heel of the club away from the ball.
Likewise, getting more vertical in your backswing restricts the club from how far behind you it can get, thus making it much harder to get shallow and more in front of you on the downswing.
