I agree with others commenting about ego, something i learned that must be put aside in order to get a proper fit as well. For years I played stiff shafts, all DG s300, in different brands of irons, and was a 6 HC. My problem was the dispersion. I broke down and got fitted using my irons (Mizuno MP 59) by a Mizuno rep. After hitting countless balls and shafts, the issue I had was loading the shaft. Even though I swing my 6I at 91 MPH my tempo is moderate and therefore i load the shaft later in the swing. I went from using an S300 to a NS Pro 1050GH R+ shaft. I became more consistent with my irons after the switch