First this: Based on long experience [that includes "book learning shit", working with all kinds of players, empirical research, thousands of hrs. practicing "doing it"] ,the question of "if" is settled ,i.e., this IS a defining of elite hitters!
And as regards this: "then we must find additional ways to train this skill.”
Well, I can only say that I have been addressing this question [as a teacher] for about 15 or so yrs.
And as such I dare say, I have developed some pretty effective ways to address said issue.
Before I make some cursory suggestions about what CAN be effective, let me talk a little about what is NOT going to be effective:
First and foremost as to what is NOT effective: VERBAL CUES. Elite level hitters, as implied by the initial quotes above, in effect, know how to "let the ball get deep."
They have, over time, figured out, how to create movements/muscles actions/postural dynamics, which, in effect, allow them to "wait longer and turn quicker" [my phrase].
Which translates into the ability to allow the ball to travel deeper, thus waiting slightly longer, yet within that reduced working time and space, optimize quickness, batspeed, barrel accuracy.
Relative to almost ALL of those who try to swing a bat, this amounts to an extraordinary accomplishment!!
When this extraordinary accomplishment is juxtaposed against the verbal cue issued to the typical little league hitter of ..."hey Johnny....just wait longer", from my vantage point, the utter ignorance of this cue cannot be overstated!
As I have stated MANY times as regards this cue in this context: "Little Johnny" has NO CLUE as to how to wait longer /but swing better; he is an "arm swinger" and as such the apex of his momentum is developed at least a foot beyond his lead foot.
Simply put, Little Johnny has a motor learning strategy problem that will not and cannot be solved by verbal cues.
So. What CAN possibly work? Simply put [without going into details as regards motor learning theories/applications----subject matter that I have spent YEARS and THOUSANDS OF HRS. researching/applying].
Simply put: "Constraint based" methodology, ie., creating methods wherein the hitter is PHYSICALLY CONSTRAINED in ways that better force the hitter to NOT do ....what they normally do.
Meaning that in this constraint based construct, you start, NOT by trying to do the right thing, so to speak. But, by trying to deter the wrong [normal/typical] thing.
This kind of training/teaching thought process IS complex. And as such not really the subject matter for twitter!.
So, for now, I'll simply reduce the process to this: The goal is that in constraining effectively the bad movement, the good movement is given a much better chance to "emerge" [a dynamical systems frame of reference].
The plate as a frame of reference is thoroughly erroneous. From my vantage point, in the context of assessing the contact point in terms of efficiency [conforming to the "Pcrw" standard] THE frame of reference is the hands/knob alignment, relative to the base of support.
"Base of support" meaning the lead leg [half of the base of support], i.e., the lead foot, knee, and upper thigh the combination of which create stability/support of the trunk/arms/bat's rotary motion.
A very key parameter of measuring efficiency or said another way----optimizing connection/maximal momentum transfer from body to bat--- is limiting the displacement of the hands/knob.
Well, first things first and conforming to my developed sense of "questioning the premise" I'll say this: The "lean back" is a RESUALTANT, i.e., it is an EFFECT of prior movements/muscle actions. And as such, it has ZERO "contribution" to any so-called "adjustment."
Thus, the obvious implication of what I am saying is this: From a causal---and most importantly---a TEACHING perspective THE most important question is along the lines of:
What movements/muscle actions/postural dynamics are involved in optimally "lining up" with a low/outside location?
A recent comment from "slay" asking as to how to 'weed out' subjectivity" prompted me to cite this interesting/relevant chart that very much pertains to this question.
The context of slay's question was me stating my skepticism as regards the so-called "fact-checkers."
I said this: ""fact checkers" ...one should be highly skeptical of those who claim this as an objective category. Recently [in court] Facebook admitted that their so-called fact-checkers were protected under 1st amendment OPINION interpretations [see Stossel vs. Facebook].
This is a clip that has been around awhile [I'm reasonably sure that someone put it on the Setpro website likely around 2004 or so]. It's a clip illustrative of things I have learned to see ---and try to teach-over the yrs.
I'll list/describe some of these functional characteristics.
1] Note hip rotation INTO foot plant ,ie., the hip rotation actually starts AS the lead heel starts to drop. That, as opposed to getting to full heel plant, stabilizing the lead knee, THEN starting to rotate.
2] Note that the lead heel drop and the back heel lift/back knee flexion happen essentially simultaneously. And these actions occur essentially simultaneously with the hip rotation.
Well, as I have explained many times, I'm a simple guy. In football I liked to hit people [had I played college football and stayed healthy I have no doubt that I would have been drafted as a strong safety---I was a better football player than I was a baseball player].
As regards baseball I was drafted as a hitter and of course my favorite part of baseball WAS hitting. And from an early age I gravitated towards drummers and drumming [my dad played as a hobby and introduced me to African and jazz drummers when I was 6].
Bottom line----and what all 3 have in common---I very much like to HIT SHIT!! And here's a guy who also likes to hit shit [one of my favorite drummers] Gergo Borlai:
And let me preface my comments here by saying that, yrs. ago I became known by members of Setpro as a guy who understood the Setpro info well enough to convey it in a very accurate manner.
The back story, so to speak, on my coming to this point is this: I had been out of baseball for many yrs. [I did not even watch baseball for yrs.---until my wife signed up my only son to play and he, over time, became a huge fan of Ken Griffey].