I've been working a lot with trying to keep the thumb down on my left hand to minimize shoulder rotation. I find that when I execute properly, the swing feels effortless, from the shoulder, I don't pick my head up, and the ball reads the lane like a dream (not the ball lol).
My issue is trying to get the hand to rotate from thumb up while holding the ball in the stance to thumb down. Almost like my non bowling hand doesn't know when to do it. I know it should probably be down by the time the ball passes the leg on the downswing, but I either do it immediately (which makes my shoulders not move at all) or too late (which negates the movement.)
Should I just do a foul line drill with the non bowling arm in position and then feel it that way, or does someone else have any suggestions. I feel like this step will be the next breakthrough in my game.