I've been working hard with the book, exercises in the appendix and DVD, and had lots of great results. I'm a bit stuck on this: The right side of my groove is higher than the left. The doctor said it was the erector spinae built up. I had a terrible leg injury for which I compensanted, so I think it is related to that. I'm not sure how to get rid of this uneveness. It's nearly impossible for me to do the inner corset drill without deepening the groove, although it deepens less. I try! What can I do to fix the unevenness?