[Daryl]

The shaft kicks before impact in every properly fitted shaft. The trick is to get a flex that gives as a straight a shaft as possible at IMPACT for face control. As a general rule, too stiff and it kicks too early, too much flex and the head lags the shaft at impact holding the face open. In those photos of Woods, he hasn't lost lag pressure, the sweetspot is outrunning the shaft, but not his trigger finger(pp#3)!

How does the shaft know where the ball is located?

The Shaft isn't programed to act on its own. It will bend from pressure and release when the pressure subsides.

Does it make sense that the clubhead may not be increasing speed but that the clubshaft has stopped accelerating.

Consider this similarity. If you cast a weight with a fishing pole, it bends in the direction of the lagging weight. But as the pole begins to slow, the weight passes and the pole reverses its bend in the direction of the weight which is now moving ahead of the shaft.

It's important to note that the weight begins to lose speed as soon as it becomes in-line with the pole. "Law of the Flail."

The downstroke Acceleration Sequence really works and it's not too difficult to learn and use. Naturally, a complete examination of the DAS is included in my Video, "The Right Forearm Participation in the G.O.L.F. Swing".