The Downstroke Pivot is characterized by On Plane Right ShoulderTurn (toward the Ball) as led by the HipTurn (motion) and Action (work). This Pivot puts the Right Elbow On Plane, and, therefore, the Right Forearm (and #3 Presssure Point) also On Plane (pointing at the Plane Line).
All this is prelude to Release. That is, the Left Arm overtaking the Right Shoulder Turn; the Right Elbow straightening; the Left Wrist Uncocking; and the Left Hand Rolling. In other words . . .
The Pivot Delivers the Loaded Power Package (including its bent Right Elbow) to Release. Then, the independent motion of the Arms, indeed, the entire Power Package, continues that Delivery from Release (via the straightening of the Right Elbow) to the end of the Follow-through.
Im still noodling this one over: When does the Right Elbow/Arm get back on plane going down?
Its on plane at Fix, assuming a RFFW. Its on plane at Impact assuming a RFFW. Its not on the Inclined Plane at Top (the plane of the Right Wrist Bend, the RFFW is still intact).