Preserving accumulator #4 lag further into the downswing will promote horizontal hinging. In plain english: Let the left arm lag more behind the pivot throughout the downswing. Don't drive with your right hand.
Works for me anyway.
I guess I misunderstood the question. I answered what it takes to promote horizontal hinging.
A Flat Left wrist is very important, even with a Strong turned left hand as a grip. Think of Flat as "not cupped" at Impact. What is important is the shaft and left arm being in-line. It forms a back-side Flying Wedge. It could be seen if you extend the shaft line under the left arm. This rear flying wedge is in-line at Store or Release, 8-9, in-line at Impact, 8-10, in-line through the Hinge Action to Follow Through, 8-11. Regardless of grip. That is the rhythm of the RPMs and acc#3- Transfer Roll. Transfer Roll is Arm and pivot produced.
Yep at Impact . . . with a Turned Left Hand . . . it's Flat AND TURNED. So whatever amount you have it Turned at Fix that is your "geometric" Vertical. So in this case Turned IS VERTICAL.
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