I agree with HB here, never use the left hand "alone " to manipulate a Flail Action or a Hinge Action for that matter . Hinge Action is defined by the Left Hands alignment to one of the three basic planes but its not done by the Left Hand!! The entire Primary Lever moves as a unit. Everybody gets this wrong at first, some never move on . Elk , some GSED's talk about full rolls , half rolls of the left hand etc but that's not quite right , close but not correct .
Quote:
Ball Behavior (p. 100)
The Hinges are actually “mounted” at the Left Shoulder but the real control comes with moving or holding the Left Wrist in the positions called for by the respective Hinge arrangements. The Hinge Action Control is required only from Impact to the end of the Follow-through. Except, of course, when the Stroke Pattern Wrist Action dictates otherwise.
The Left Wrist is controlled by the On Plane Right Forearm Wedge and its Angle of Approach while moving toward Low-Point.