Then flip the switches.
Note: I understand that the reason for the appearance that AlphaGo does not have a large margin earlier in the game is quite different. I simply see a plausible parallel with your observation regarding the game of Go and the scenario of superintelligence take over, if we develop them wrong.
What I think is really going on (and what will actually happen if a "robot takeover" happens) is the computer just does its thing, but because it's so powerful, it's out of reach of any human being's understanding, and people think they are pulling some trick.
Machines can win without using tricks just based on their computing power.
Yesterday I heard one of the commentators say something like "what i liked about alphago today was how effortless it's playing. It's almost like it's just playing happily and not even trying hard, giving away losses happily when it comes to it."
Alphago has no emotion, but just like how human beings look at something that walks like a duck, quacks like a duck and conclude it's a duck, humans interpret everything based on their point of view, thinking "I can actually feel what alphago is feeling, just based on its moves".
Another thing they said was something like "there's a high level player premium", meaning when people play against other people, they can't ignore all the subtle little queues, such as how much time they're taking to come up with a move, whereas Ke Jie has no such thing against alphago because alphago doesn't care. (Whereas Ke Jie does care)
I think if anything, that kind of emotional vulnerability is what will bring human down against machines.
It brings to mind the old quote, "the only way to tell the difference between genius and madness is by the results."