By Mike Epstein

Approach to contact
Having his weight balanced, or 60-40 over his front foot, will facilitate the dropping of the front heel. Straightening the front leg drops the front heel. As the front leg firms up, the back leg begins to bend slightly at the knee. Equal-and-opposite. 
 
Dropping the front heel initiates hip rotation. It pushes the front hip rearward as the back knee begins bending and slightly turning down-and-in. Equal-and-opposite.

His lead elbow then begins to work up, and his back elbow begins tucking in close to his body. Equal-and-opposite.
 
His body begins a slight tilt rearward as his front leg pushes back and straightens out, initiating the swing, and blocking any further movement forward.

The back elbow tucks down-and-in (for the hitter to be able to stay inside the ball) as his swing begins. Since the back elbow is down-and-in, physics dictates the front elbow work up-and-away. Equal-and-opposite. 
 
(If the rear elbow doesn't tuck down-and-in when the swing launches, the back arm will pre-extend outward, resulting in a "casting" motion. When the rear elbow tucks down-and-in, the lead elbow must work up-and-away. In other words, for every action there is an equal-and-opposite reaction.)

As the swing continues forward to contact, the cumulative weight of the hands, arms, and bat, must be counterbalanced to maintain the hitter's balance, or else he will continue coming forward. The dynamic counterbalancing move made by the body is its rearward tilt which continues adjusting to the pitch location. Equal-and-opposite.

Contact 
The front leg, which began firming up in the approach, ultimately becomes rigid at contact. The dynamic counterbalancing move to the hitter's rigid front leg at contact is his back leg softening and bending. This enables the hitter to maintain his balance—despite often being behind his initial axis of rotation (depending on pitch location). Equal-and-opposite. 
 
Follow-through
Contact is made with UNBROKEN wrists. 
 
At swing launch and the subsequent approach phase, the rear arm is tucked down-and-in and the front arm is up-and-away. Equal-and-opposite. 
 
AFTER contact, the hitter's arms reverse themselves: the back arm becomes up and the rear arm becomes down. Equal-and-opposite. 
 
The front knee then naturally flexes enough to bring the tilting body forward to maintain balance in the follow-through. 
 
If the hitter has trouble with his balance in the follow-through (on a pitch where he was not fooled), the remedy often comes in the form of a question/suggestion by the instructor: "Why can't you stay balanced in your follow-through?"/"TRY to maintain your balance in the follow-through." 
 
Linear hitters rarely were balanced in their follow-through and therefore being unbalanced became an accepted part of the technique. Hitters transitioning to rotational hitting from linear hitting will often continue to be unbalanced in the follow-through unless you remind them that they CAN maintain their balance-point if they concentrate on doing it. The problem usually then goes away, although constantly reminding them at the outset is a good practice, until it becomes second-nature to him.

Prior to Mike’s teaching years, he was an All-American baseball player and still holds the highest lifetime batting average of .384 at the University of California (Berkeley). He was a member of the first United States Olympic Baseball Team, leading the team in many offensive hitting categories (Japan, 1964). He was named the Sporting News and Topps Minor League Player-of-the-Year in 1966.His website is http://www.mikeepsteinhitting.com/