Umpires aren't perfect. Nor do they pretend to be. Nobody disputes this fact - blown calls are currently part of baseball. I can't imagine that many people think that this is a good thing, either, despite the outcry over the possible dehumanisation of the game that comes with instant replay and (horror) the possibility of computers calling the strike zone. Getting a call wrong while arbitrating the highest level of competition of a major professional sport simply cannot be a good thing. Umpires may be right 95% of the time, but we are capable of improving that, and it seems to me that we probably should.
Calling for an end to umpires is not a reasonable answer, though. The men behind the plates screaming for balls and strikes have become so entrenched that the sport would seem frankly silly without them. I trust pitch f/x, but not to the point where I want to see a monitor behind the plate calling balls and strikes. And I'm not even a baseball purist. Grown men start foaming at the mouth over suggestions like doing away with umpires to get the call right, or instituting replays on questionable calls, and guess what? The people who think that way are the ones who matter.
Fortunately, "robots" is shorthand not for "we want robots to make the calls" but "we would like greater accuracy from the people making the calls". There are ways of increasing accuracy without compromising 'the human element', or slowing the game down for replays. Here's an idea: pitch f/x as a tool for umpires, rather than being the judge and jury of ball/strike calling.
How? Well, home plate umpires already wear masks. This gives us a really easy way of giving them quick information without compromising whatever else they're focusing on. Frame their field of view with LEDs, throw a wireless receiver in there, and a lightweight battery. Now write a program that takes pitch f/x data, translates it into ball/strike/borderline (i.e half a ball diameter off the black) calls, and transmit it to the umpire in real time. You could do this with minimal lag - I doubt anyone would notice the difference if umpires reacted solely to the colours the inside of their masks flashed at them. But the beauty of this plan is that they wouldn't be reacting solely to the colours. They could use their own judgment on borderline calls, they could request that their strike zone be different with lefties and righties, etc etc etc. They could use pitch f/x as a guide to help them call the strikezone as they see fit.
Who does this hurt?
The fans wouldn't notice, and they wouldn't have to be upset over as many blown calls. Pitchers would see a more consistent zone, as would hitters. Umpires would still have freedom to call their own strike zone, and I think they'd be happy to have a tool that improved their accuracy. We'd still see zones widened on 3-0 counts and we'd see pitchers throwing perfect games be given the benefit of the doubt.
This would not be a difficult thing to do. I'm pretty sure that given a month with a pile of electronics and a computer being fed data from the pitch f/x source I could rig up a prototype mask that would do exactly as I've described above. With the resources MLB has, it would be simple to get something like this plan set up for trials in next year's AFL.
The heart of baseball - calling balls and strikes - could be officiated better for not much more cost and without taking away from the beauty of the game. Why not give it a shot?