[Bigwill]

Try to not turn your hands off of their vertical to the ground alignment in the backstroke and let the gyroscopic motion of the clubhead turn your hands towards the plane for you. Don't actually try and turn the left hand towards the plane....

Use the pressure from extensor action towards the plane line. As you turn your shoulders your hands will automatically maintain their relationship with the plane line bringing the club up the inclined plane. Body turns and the arms swing upwards.....

So, in order to stay on plane, someone with less turn would need more "in" with the arms in order to compensate for what ever isn't provided by the pivot? Or, conversely, someone with a very large shoulder turn would need more "up" with their arms (relative to their body) in order to compensate for a big pivot rotation??