For years, various teachers would tell me to get my back straighter and to position my chin higher, I ignored their advice, they got pissed, and I went on to other teachers.
Finally, I was so comfortable with my swing which was smooth and my ball flight and scoring, that I abandoned teachers and went on to compete at a good level in local and national tournies.
Moral of the story: listen to Brian and do what feels right for you. The results are the only thing that matters.
You shoulder turn is too steep.
Try making backswings FEELING LIKE you right shoulder never gets any high than it was at address.
New Research shows that you can get your back too straight. Whatever you do, don't stick your butt up in the air, and don't hold your head or chin up.