1
...before taking his trigger step and beginning his hip turn?
As you correctly point out: "It simply isn't possible to read the pitch and then transfer the weight"
And we might conclude that better is the hitter and shorter will be distance of the ball from contact point when he decides to stop swinging, since a pitch usually reveals its real flight path only late. In other words a good hitter first of all is defined if he attacks every pitch and then by how and when he stops swinging. Barry Bonds was simply exceptional in this.
I believe Ackley could be very soon able to attack the .400 mark - if just he wants to.