Birdie, here are Wishon's comments:
Tom Wishon's Opinion on Maltby Playability Factor ( MPF ):
Just back from the PCS Show and this was one of the topics of discussion among the clubmakers since GolfWorks does push this on clubmakers. I've stayed pretty low key about this in forums and other public commentary places, but because of your question on our forum and because of some of the total mis information that I heard from clubmakers about this at the PCS Show, it's probably time for me to offer more direct comments.
It is certainly a noble venture to attempt to create a ranking method of playability for clubheads, but it must be done on the basis of 1) proper application of ALL Of the possible scientific aspects of a head design which can contribute to playability, and 2) it has to be backed by real performance testing to verify the rankings derived from static measurements of the design parameters of each head.
NEITHER are done even close to properly in the MPF.
For one, the MPF completely ignores a handful of very important design parameters that have a definite effect on the performance of a clubhead. For one, they ignore the rear CG location of the head, another one they ignore the MOI of the head about the axis of rotation about the shaft, and they also completely ignore the contribution of the face design for off center hit forgiveness, instead putting all of their emphasis for off center hit forgiveness on the MOI of the head about its CG axis. That is just plain poor science on their part and if the industry were to want substatiation of that from other expert engineering sources, Tom Stites who is Nike's designer and Clay Long who is an independent designer currently doing all of the Nicklaus designs have both gone "public" with the same statements of poor application of the wrong scientific principles. Prior to doing NIcklaus' designs, Clay did all of MacGregor's models in the early to mid 90s and all of the Cobra designs in the mid 90s to late 90s.
Second is the fact that once the MPF was created on paper, no real hit testing was ever done by GW to verify their on paper premise for playability. Therefore, this system exists strictly in theory, and poor scientific theory at that because of the design parameters which are ignored.
So in the most simple terms, the MPF is defintely a worthy project to try to tackle for what it intends to do, but in no way can it be trusted to ever guide clubmakers or golfers into what really would or could be the best clubhead design.
TOM
Here is a quote from Matt Mohl, who works with Tom Wishon: " The biggest hole as I see it, is that they never tested their hypothesis and led people to believe that there were differences based on a number without anything quantifiable...And (that) they used it as a marketing and sales tool to rate other companies heads..."
