I think replay makes sense on only certain types of plays, like whether a home run ball is fair or foul, or hit above or below a line on an outfield wall designating a home run, or a call at first base like the one that ended the World Series, when the first base umpire correctly determined that Orlando Palmeiro was out. But ball/strike calls or judgment calls would be exempt
.www.boston.com/sports/baseball/articles/2005/10/30/should_baseball_use_instant_replay/