fatsensei, that’s been a problem area for me as well. After going to 3 different chiros (one an ART-type), an accupuncturist and a number of massage therapists (some of whom made me worse!), I found a lady that has 14 years of experience with myofacial release technique who pretty well fixed my problem. My posture is improved, along with biomechanics. Now it’s just a case of re-building and strengthening.
Good luck to you!!!
P.S. I had impingement syndrome and torn rotator cuff (supraspinatus and infraspinatus, both) surgery a year ago. Even with surgery (or maybe because of it), my rotator cuff muscles were in need of some attention.