Ginger is exactly right when she wrote, "the higher-under-the-armpit armhole actually gives far more range of motion." Proper shoulder fit is my bête noire, and like you NM, I have broad shoulders and a small chest. I was moaning about jacket fits to my seamstress, and she had me bring in a few. I had been buying them too large to get what I thought was greater range of motion, since my correct size felt too small across the shoulders for me. Using a jacket I had just bought that I thought was too small, Fatima adjusted the armholes higher by hand, and magically, I had complete range of motion. Mind. blown. I so love my seamstress!!