Thanks. I suffer from the same underplane severely inside move. And I can see how some left bend would keep you more upriight. But when do you add the left bend? And wouldn't this result in a dip or lean toward the ball with your head when you're rotating back and thus a change of spine angle?
at address, you are bent over, very approx. 60*, from dtl view.
now, as you get to the top, if you maintain some of this waist bend, then your left love handle will sorta bunch up (more if you have a little substance in that area
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). from dtl view, depending on the hip slant, left leg position and amount of waist bend, there will be around 100-110* angle between the left side of the chest and theleft leg. this is left side bend.
if you are a hooker, then trying to keep this angle into the downswing can keep the club more infront of you help you trace a plane line thats more to the left. i think brian calls this the "no tilt until after the sit-down" type downswing