If you want to try the Big Break or anything that requires perfection, I would highly recommend finding a TGM'er. They should be able to give uncomplicated ideas, but still give you the same information.
The rotation in the downswing "Duval like" does not allow the overtaking of the right arm. Angled hinging is a neccesity for hitters. The pushing of the right arm closes the clubface.
When you play with a turned grip for too long, you'll always try to fight off the left shot with rotation. Those are mismatched components and are sometimes mistaken for clubhead lag.
If you truly have professional aspirations, come see me, Yoda, or Steve Ferguson. It will be worth the trip, even if you live in Australia.