Commentary for black move 3:

Mr. SEIRAWAN: The average length of time, the time control, is 40 moves in two hours for the first session. To be clear, it means that Deep Blue has two hours of thought to make its first 40 moves. Then, one hour to make its next 20 moves, and then a half an hour for the rest of the moves for the third time control. Is Deep Blue thinking when Garry is thinking?

Mr. VALVO: Definitely. And you should build into your formula that the computer has to reserve maybe 20 minutes because it might break down and they have to replace it with another machine, and that all counts against them so they don't really have the full two hours in terms of thinking. They have to have that reserve time in case something goes wrong. But yes, they are going to be thinking on Garry's time. What they're going to be thinking about, however, is they're going to guess the best move they think Garry can play, they're going to analyze that. If Garry doesn't play that move then all that thinking is wasted. So the next question is, how often do they guess right? How often do you think they guess Garry's move? AUDIENCE MEMBER: 50 percent. ! 50 percent is correct. The computer guesses Garry's move 50 percent of the time.

Mr. SEIRAWAN: That's tty amazing.

Mr. VALVO: Pretty amazing. That means they get twice as much time for that move.

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