The feet moving is a reaction to how hard his feet are pushing against the ground.
i.e reaction force
He’s not trying to pull his feet away from the ball
It’s mostly coming from the lead foot pushing down into the ground and in direction of where lead foot is pointed (approx)
@mark_immelman @MiracleSwing Repeat after me, shallowing has nothing to do with hitting a draw or a fade! Shallowing happens when you transfer your weight properly or have proper sequence. That’s the end of my Ted talk thanks for listening.