Now, I rarely watch the show anymore. Somehow all the fun goes out of it once you've had your shot and lost. So I haven't seen this guy, but I will say this: there's a definite rhythm to the show and to working the buzzer, and the more practice you get, the better you are. Here's how the routine goes: the question is revealed and is clearly legible by the contestants. Alex reads the question out loud. The instant he is done reading a guy offscreen pushes a button that unlocks the buzzers. Buzz in before that, and you're locked out for something like 2 seconds. It took me a couple of minutes to get the rhythm and then I started to dominate. The other thing I realized is that all three contestants know the answers to probably 90% of the questions, so the whole show comes down to buzzer control.
Now, here's the shocking secret of "Jeopardy": Alex blows the question reading a couple of times per show. He mispronounces or fumbles or something. What they do then is have him re-record the questions during the commercial breaks (the shows are taped real-time). Notice that you never see Alex read the question.
Occasionally too, you'll se him go on a roll when even he is better than usual at buzzing in. He will often buzz in at these times without a clear idea of what the answer is, he just thinks up an educated guess during his 5 seconds, whic is usually correct.
It's just a case of a really smart guy who has working the buzzer down to a science - just as you'd expect a trivia-expert computer geek to do, given multiple chances.