I have been looking at these alignments for three years. Sometimes BG gets his Plane Line a bit right, but usually it's dead on the money. When it's not, it only takes a few swings to get it back.
Take a look. Emulate what you see here -- especially the overall Body Posture,Centered Head, On Plane Right Forearm, and Level left Wrist -- and watch your scores go down!
#1 Address with Iron / DTL View / Note the usual alignments: Body Posture. Bent Right Elbow and On Plane Right Forearm. Level Left Wrist. Also, the Head position. No 'chin-up' here. BG is looking directly at the ball.
#2 Address / Front View / Same as above.
#3 Follow-Through and Swivel into the Finish. Note the free Arm Swing (Zone #2 Power) and the 'well down' and On Plane Right Shoulder (Zone #1 Pivot). Even at this late stage, the Hips and Shoulders are "comparatively squared away". That is, there has been no gross inward Pivot Movement to pull the Hands (and Club) Underplane. Feet and Knees support the Action. They do not cause it.
#4 Finish. Check Hands Location, Body Position and Balance. The Left Arm Flying Wedge -- Left Wrist alignment and Clubshaft in-line with the Left Arm -- is hidden from the camera, but it remains an important and integral Finish alignment.
#5 Address with Driver. Note the above alignments and, also, the correctly soled Club with the ball slightly toward the toe of the Club.
#6 Chip Shot -- through the ball. Centered Head. Ball back in Stance (Up Plane). One Lever Arm Power only. No 'Hand Action' Power.
#7 Address for high, soft Pitch Shot. Centered Head. Open Clubface. Ball forward (Down Plane). Square or slightly Open Plane Line, depending on the Lie and desired ball behavior. Compare Grip and Clubface with #2 above. Cut Shot Action: Backstroke Left Wrist Turned, but No Roll through Impact.