[EdZ]

Ahh. Procedure #1 is a Sequenced Release, but, Procedure #2 is a Simultaneous Release (using a Bent Left Wrist and Flat and Level Right Wrist).

Procedure #1 is status quo and includes nearly a 1/2 Roll of the Left Wrist from Release to Impact. The Double Wrist Uncocking, procedure #2, is a 3/4 Roll of the Left Wrist from Release to Impact.

Given an On-Plane Clubshaft during the Downstroke, it's not a simple Rolling of the Flat Left Wrist like a rotation around the left forearm as in Procedure #1.

I'm sure that it evolves into a Procedure #1 Roll after Impact, but before impact, the Flattening the the Left Wrist, simply moving from Bent to Flat, is Rolling around the Sweetspot on the Clubshaft. Because Uncocking and Roll occur Simultaneously from Release to Impact, they both rotate around the Sweetspot Plane.

Yep, that is where I thought you were going. A snap release/automatic.

BTW - in addition to the above discussion, the pics you posted are one of the best sets for explaining horizontal hinging for those that are still foggy.