I don't know why this manifesto is more popular than any other anti videogame manifesto out there - http://www.pointlesswasteoftime.com/games/manifesto.html - for the most part I agree with it. But that very first one, that AI should surprise us, that's a case of "You think you want that but you don't really want that." One of the reasons we make game AI stupid is not always lack of processor power but often because a smarter AI would school our players too deeply and they'd turn to simpler games. Look at chess - we've got some great AI there, so great nobody wants to play against the computer. Stealth games would be another example: if the security in a stealth game actually was decent, playing these games would become an exercise in frustration instead of an exercise in feeling like a kick-ass ninja commando.
Perhaps, better worded, the goal would be: "Give us an AI that surprises us, gets us on the ropes, but still lets us win the day."