Wondering if you have measured the Wilson D7 iron heads and what prelim MPF is.
First, thanks for catching the error on the Callaway page. We will correct it. As far as the Wilson D7 being conventional, your guess is as good as mine. I do not think all the manufacturers consider the MPF when designing. The category a club ends up in is totally dependent on the mass and dimensional characteristics of the design. Ralph developed the MPF as a way to identify these characteristics and how they effect playability, and put them in categories so golfers could have a way to TRULY identify how playable a club may be for them. I do believe that the MPF has influenced some manufacturers in how they design, but still there are many that may not identify with it on every design and thus may not design the features in such a way that yields a higher playability category.