Observation / Hypothesis......I have zero scientific leg to stand on so this is just a "pondering"
I notice at the 6:30 mark the good accelerating stroke ball picked up forward rotation before the others...That seems to be a significant difference IMO....I wonder if the same effect would happen on draw (struck in the same spot)
I wonder if there may be some difference (from timing) due to shaft flex....I can't see how that could be measured but I suppose high speed cameras could pick up the flex.
I know in Golf shaft flex/stiffness, make a big difference based on swing speed....You basically want the whippiest shaft you can control ....Shaft too stiff and the ball comes off like a brick....to whippy and you lose control.....(add innuendoes here gutter brains....

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I realize that the forces are applied in different directions between a Golf Club and Pool Cue....But I tend to want to think that shaft flex/taper etc....like in Golf play a significant role in the amount of "action" you get on the CB....and quite possibly could be a reason that some people swear they get better action from cue to cue or shaft to shaft....
Also a similar trade off in Pool....Perhaps a stiffer shaft....The CB comes off like a brick with the wrong type of stroke....whippy shaft...(AKA Meucci)...all kinds of CB action but hard to control.