Over the last year or so I've developed an overswing that I can't get rid of. My takeaway is good and the wrist s cock well. My shoulder turn is 90*. But here starts the problem. For whatever reason my left arm breaks down and its as if I reach back another foot at the top. Not only do I catch sitght of the clubhead from my left eye but also most of the shaft. From here to get it back to the impact zone takes remark able ability. Alas it doesn't happen often. What can I do to stop this?