He comes off as so full of himself when he claims that the original programmers didn't know about the different ghosts' "personalities" (algorithms).

He's referring to this: http://home.comcast.net/~jpittman2/pacman/pacmandossier.html...

And there's just no way that the game's creators didn't know how they programmed the behavior of the ghosts. More likely they were humoring him and he took it as him "knowing more about the game than its creators" or whatever the quote was.

Plus, I would never claim to be able to execute a perfect score (or even a very impressive one) but I can definitely put Pac-man into a blind spot. His claim that "you couldn't do it even if I told you how" comes off as pretty egotistical.