We know that Master can figure out what it would play. We also know that its predecessor had a model for what moves a human professional would be likely to play.
What I would find truly fascinating is if Master could divide moves that it plays, which professionals wouldn't, into groups based on a similar internal categorization of the moves. And then see if human minds can look at any of groups and come up with a human understandable principle that humans had been missing about the game.
The point here is not so much to improve human play (though it presumably would do so), but as a step towards having an AI that can break down its internal model into principles that can be used to train another AI to learn those principles. Just like how a human expert can learn to turn expertise into something that can be taught to other humans.
This has several potential benefits. The first is that human experience suggests that this type of introspection tends to improve our own competency. The second is that we could have a single AI trained by multiple specialist AIs to get a compact "generalist". And the third is that this is a path towards having AIs that can discover things then teach them to humans.
The whole idea might fail horribly. But I'd like to see it given a shot.