I had a fitting with the Titleist rep at my club last fall when the new AP1s and 816s were released, and which I like the forgiveness of the 716 AP1s, I ordered a lot of clubs, yet I developed some bad shanking habits with the new irons that I never had before. I have done all kinds of lessons and analysis on my swing, and while its not perfect, I recently believe that it was because I was "custom" fit into the wrong shafts -- the NPS 950 Pro shafts stiff. I realize these are probably great shafts, but I recently went to a fitting for some woods, and the fitter saw my irons and had me try them with the stock XP 90 reg shaft and no shank, no problems.
In sum, from what I have been reading, being in a too heavy and/or stiff shaft can promote hitting too close to the hosel and question if I was fit properly, with the wrong shaft has contributing to me not being able to square up the clubface. Can Titleist help? Not placing blame, just losing confidence because this is a problem I NEVER had. Thanks.