The commentary from Redmond was illuminating for me, in his estimation having played against monte carlo simulations before, at that point the computer just pla

The commentary from Redmond was illuminating for me, in his estimation having played against monte carlo simulations before, at that point the computer just plays very low probability moves with extremely high outcomes if the other player makes a grievous mistake. So the moves looked terrible since the 'retort' is obvious, but if for some reason LSD didn't play the obvious counter, it would catapult Alphago back into the lead. Of course since LSD is an expert, he never missed the retort, but very interesting behavior nonetheless.