I think the main issue with your initial statement was that you said you could beat someone just taking AlphaGo's advice on every move. Usually when people talk about opening books, they think of the opening book as being part of the engine's decision making process, not an addition to it. Usually this is literally the case, as in chess where I can add an opening book to Stockfish's runtime options.
In my opinion, it's really strange to describe this as an expert "beating" AlphaGo, when really it's just a technique for making AlphaGo stronger than it is without a huge pre-calculated cache of moves.
In my opinion, it's really strange to describe this as an expert "beating" AlphaGo, when really it's just a technique for making AlphaGo stronger than it is without a huge pre-calculated cache of moves.