I don't disagree about instant replay, and I can see making a case to leave the strike zone in the exclusive jurisdiction of the umpires, at least until there is some sort of three-dimensional tracking system available (I'm thinking of a chip in the ball, and the batter's uniform shirt and pants, and sensors in the plate) to determine the strike zone for review. However, I wonder if that might lead to, for instance, more decisions to swing away, even at bad pitches. No umpire's blindness or prejudice or favoritism can overturn the bat hitting the ball, and if the batter or his team thinks it is better to take their chances with replay preventing trapped balls in the outfield masquerading as catches, and determining fair or foul balls, and preventing basemen from leaving the bag and so on, they might more inclined to swing, rather than let the umpire call BS strikes. And too, a pitcher might be more inclined to take his chances with accurrate calls in the field, rather than have a strike on the letters called a high ball.