Posted by: Jack Mankin (MrBatspeed@aol.com) on Wed Jun 16 11:58:24 2010

>>> I like your work a lot and I like Chris O'Leary's work a lot too.
Both of you have helped me a ton. But, I have to believe you are more correct on the hand torque issues because I do see the video evidence, even on Chris' web pages where he refutes THT. <<<

Hi Joe

One of Chris's quotes you posted states, "In a rotational swing, the hands, wrists, and forearms do not generate any force;"

If I read the meaning of his quote correctly, he is saying the arms, wrist and hands serve only as linkage to the rotating shoulders with no ability to impact the bat's acceleration on there own. I would agree that providing linkage to the rotating shoulders is a major function of the arms. This would be especially true of the lead-arm which remain in a fairly fixed position in relationship to the rotating shoulders.

However, the direction of pull and rotation of the back-forearm and hand can provide torque that greatly impacts the bat's acceleration and trajectory. -- I read a thread on another site where Chris and other posters were discussing these mechanics. They were addressing a demonstration video that showed the bat-head sweeping rearward at a much greater angular rate than shoulder rotation - similar to the trajectory in THT.

Below are few of Chris's Quotes from that thread.

##
"It's sweeping the bat head rather than whipping it. Notice how early the barrel comes away from the shoulder and the hinge angle changes."

"This is sweeping the bat head. The wrists and arms are turning but nothing else is. I see it all the time in my 2nd graders and in my bad 4th graders, but not in good hitters."

"The bat head is moving away from the back shoulder from the start of the swing, which is completely wrong."

"I teach rotating the back shoulder as the first move, not opening up the hinge angle early and sweeping the bat head."

"the barrel stays in the same position relative to the back shoulder as the shoulders turn."
##

I am placing below a video clip that shows the initiation phase four hitters with what I deemed as exhibiting "Good" mechanics and also four hitter's mechanics I deemed as "Poor." The video addresses the first 4 frames (60 fps) of their initiation and note that the "Good" hitters shoulders rotate about 30 degrees while the bat-head rotates (or sweeps) rearward over a 100 degrees. According to Chris's statements, this is what he would expect to see in "my 2nd graders and in my bad 4th graders, but not in good hitters."

Chris states that in a "Good" swing, "the barrel stays in the same position relative to the back shoulder as the shoulders turn. -- Well, that's about what we see in the batters with what I call "Poor" initiation mechanics. Note that their shoulder and bat rotate about the same of degrees during the initiation phase - little THT being applied.

Four "Good" & "Poor" - THT

Jack Mankin