I don't know but Ive been told that stiffer the better. What would you want your #1 power accumulator to hit the ball with? A soft noodle or a baseball bat? I use stiff steel shaft in my short irons that I "Hit" and a softer flex from mid to long irons. I think a stiff top for #3 works well to. No answer for swing weight.
I don't "Hit" mch these days, I'm sure an answer from the Hitters will be posted soon.
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