[yodeli]

You're on fire OB, hot and boiling !

OB is right GarageFan, low point is not enough and you must go to both arms straight.

Again, you remember the example with the driver: nowadays with those 460cc heads we are told to hit the ball on the way up. So, low point in this case would be before the ball.
A common fault would be to think that because the clubhead has passed low point there is no more need to go “down” in the stroke.

Wrong!

The thrust continues down and out even after the clubhead has reached low point.
It is only because of the left arm acting as a leach that the clubhead goes up and in while you continue to direct the thrust down and out until both arms straight.