Of all things for optimization 'puring' would make the least difference in consistency. Shafts are not out of round or lacking in straightness as they used to.
So, I agree. Puring can be not as beneficial considering how good new shafts are.
The ball-bearing puring is a lazy way of doing it. I think using frequency counter is a proper method. And even with that all you are really doing is confirming that the frequency (stiffness) of the shaft is what it says it is.
If the orientation of the heavy side is made facing the target (generally direction clubface expected at impact) it may give you the stiffest orientation. It may not necessarily be the best, i.e., there's no point finding the stiff orientation spine if you are expecting a R-flex. Mind you, all of this is splitting hair in the first place.
I am not sure how any of this affects consistency of shaft kick shot after shot anyway. Any shaft is consistent to a flex level in whatever orientation it is set at - heavy side, light side, strong side, weak side, etc.
Bottom line.. hit the ball on a launch monitor and if launches and spins best then that is the purest shaft in combo with the head and grip.
I will say this that bending fatigue (flex of shaft softens over hundreds of hits..) is a real phenomenon and if you are an avid hack (once a week) then you should consider shaft or even driver replacement every 3-4 years as a rule of thumb IMHO. Of course performance would have to be your best guide.
I'm not sure if this qualifies as "best shot" or "worst shot." I was about 160 yards from the green on a par 4. I yanked it hard left and the ball hit a tree about 100 yards away and about 60 yards from the green. The ball stopped about 6 feet behind the pin and I sunk the putt for birdie.
Having ditched my 3 wood in favor of 5 wood, I decided to experiment a bit and place a four wood back in play. By wood, I mean "real" wood. I have a set of Ben Hogan Speed Slot woods that I fool around with from time to time. I find that when my game is on, the older woods work pretty well. I like the small heads although there is no margin for error. The only concern I have, and not really one that I am too worried about, is using the older woods with modern/Surylyn or Urethane covered balls. So far, I have not noticed any nicks or anything, but then again, they have not been hit all that much. I thought about buying a box or two of Balatas, but if you go Titleist, they are a bit pricey.I have not tried the other brands such as Top Flight Z, Dunlop, Maxfli, Wilson which are a little less expensive.