[Daryl]

Thanks, Daryl, I am hitting, am I zero shift as right forarm on plane at address and just bring it back and push it down. Does zero shift must be for Turned Shoulder Plane?

If you bring it back and up and then take the hands straight to the plane line without going up or down on the way, with the left arm wedge intact, then you're using a Zero Shift on the downswing. Zero Shift means no plane shift.