First things First, its important to work on being short to the ball. ie not casting the hands or the barrel. Then work on getting through the ball to good extension. There's a good saying to help remember both concepts: "short to it, long through it". it being the ball.
Greg:
I think you are absolutely right about remaining connected and taking the shortest path to the ball (a circular hand path or "CHP").
After that, I'm not so sure. I am very aware of the C.W. on extension. I own RVP, and have spoken to Slaught personally about this. I have heard Candrea and others talk about it. I have heard pro hitters discuss it on many occasions. And I have seen video demonstrating that they often DO it (but also a lot of video indicating that they don't always, too).
And please understand that I am merely curious, not being argumentative.
But I would ask, why is extension important? The ball has left the bat, and nothing the hitter does from then on will affect ball flight. Which to me argues at least somewhat for irrelevancy, whether the hitter extends, stops, stands on one foot, whatever.
Further, the ball is in contact with the bat for less than 1/1000 of a second, so little that the hitter does around the time of contact is going to have much of an effect, either. NOW< what the hitter does just BEFORE contact seems wildly important. But for that 1/1000 of a second DURING, or anytime after? It doesn't seem important to me. I mean it certainly SOUNDS intuitively obvious. And SOUNDS right. But is it, really?
Please understand this is a different conversation than decelerating into the ball, which is obviously wrong. But that said, if you do a Tee Drill with properly executed STOP Swings, I think you'll be stunned by the resultant whip and bat speed. IMO, this is the explanation for why people often observe - and comment on - checked swing HRs. The phenomenon is often attributed - typically derisively - to a hot or illegal bat, but that is not my experience. A sudden STOP to a well-connected swing does result in a whip of the end of the bat.
So does tightening the radius of the swing arc, which is difficult to do if you extend very far past contact. Paul Nyman of Setpro used very sophisticated engineering / physics software to demonstrate that a tightening of the swing radius just before contact can add as much as 40% to TIP bat speed (which is what we care about, right?). His 7-part simulation on the subject is an incredibly scholarly and persuasive work. eMail me for details if you are interested, and I will try to find a link or send you the info, though it is well over 50 MBs.
But there is a LOT of evidence that tightening the swing radius creates incredible whip. And it may be possible to tighten the swing arc WHILE extending, but I personally can't do it.
So I'd ask, assuming consistent bat speed to contact, why is it important to extend PAST contact? In fact, I'll go one further. Once contact has been made, shutting down the swing and starting to run as soon as possible would SEEM desirable just from the hugely pragmatic perspective of trying to get to 1B as soon as possible.
I am very interested in your thoughts, I think this is a great area for discussion. Not sure this is the appropriate forum to do so, as I'm not sure there is much interest. But I'm game if anyone else is. (I am heading out of town for a week, and will have limited connectivity, so may be slow in responding if there IS interest).
Thanks, and best regards,
Scott