On the other hand, in many ways AlphaGo plays much like a human professional. The openings and fights were not radically different. The professional commentators did not have a hard time explaining why most moves were good. The structure of the board was understandable. Some moves were "forced" moves that were predictable and many others were good moves that a human would play. The human player isn't efficient enough to win, but attacks and defenses still mostly work as intended.

This suggests that Go space was already very well understood and there aren't radically different play styles we've somehow overlooked. AI is not a magic wand that radically changes how the game works.

However there may be some bias due to AlphaGo having trained on human games and playing against a human. The real proof will happen when they redo the retraining from scratch.