The one plane swing requires that you bend from the hips more than the two plane swing set up. This move is counter balanced by your buttocks going back more, thus maintaining your balance on the balls of your feet.
When you are faced with a pitch shot that you need to carry over trouble but still have room to let the ball roll play a medium height shot. Narrow stance, ball centered, weight slightly forward, minimal wrist hinge, more body movement going through than
Since your body is bent over more in the one plane swing the shoulder plane resulting from the body pivot should be pointing to the ground just outside the golf ball.