Timing, timing and timing. Mostly late, emergency arm swing. Hitter must dance with the pitcher not swing faster. When the pitcher starts moving so does the hitter. Not every hitter is the same but its their responsibility to figure it out in the on deck circle or before. Steve Springer says you don't have 3 or 4 ABs per game, you have 25 or 30. Watch the pitcher and mentally prepare your timing.