I've always used the wingspan method, and to my knowledge, have never misfit anyone. Like I've said before, some bows run long on what's stamped on the cam. I know when measuring someone for a Mathews bow from the Z7 to the current models, to subtract a half inch. As Dan mentioned, a d-loop and release length all come into play.

JBC, as far as you being misfit, all it takes is one wrong number punched on the calculator to come up with the wrong measurement. The person that set it up should have recognized it once they saw you draw and anchor. I used to shoot for Archery Unlimited and I think Rick runs the best shop in the state, but mistakes do happen. The wingspan method is a solid way to measure drawlength.