The following is a quote from a very LONG article on iron head design, talking about the Cast Vs Forged heads.
"AND YOU MUST PAY ATTENTION TO THE SHAFT TOO! Even a mediocre club design configured with an excellent shaft that fits your game properly will usually perform satisfactorily for you, but the converse is NOT true! A great club head design with a poorly designed, manufactured, or fitted shaft can be completely unhittable! The shaft component in many cases (and how well it matches your game and swing) can be FAR more important than the particular club head design. Better players should focus even more heavily on matching the right shaft with a decent club head design and then being properly fitted."
As you can see by the qoute, the author is well aware of how important a good shaft that is properly fit to the golfer is to equipment performace The aurthor was Bob Reneget, the owner of Two golfequipment companys over the years.Bottom line is that he is telling everyone what I have been telling people here for years. Get a Good Quality shaft that Fits your game and have it properly installed in your golf clubs. Those OEM shafts that come in todays off the rack clubs are pretty CHEAP shafts, with and average cost for most ot them at around $4.00 or LESS. True, some of the high dollar driver do come with better shafts as an option, but even those shafts are NOT the same as the True After market shafts with the same name, and NONE of those shafts are Spine and FLO aligned before they are installed, so you do NOT get the most out of those so called shaft upgrades. .