There were blunders in the first round of games. I remember this vividly because I went through all the games with the exact same version of Stockfish with the same time controls and it thought some of its own moves were blunders. This is partly why people were so puzzled by the setup that led to this.
Hence why I talked about the feeling you get when you realise you have mis-evaluated rather than trying to define it precisely.
From the OP:
> But when AlphaZero plays, and you watch Stockfish's score, the reason it wins is that it makes moves Stockfish thinks is poor, so it rates AlphaZero's moves poorly, and then all of a sudden it has an oh shit! moment when it realises that AlphaZero is actually ahead, and its score jumps. It's really a look inside the computer's head while it's being beaten by a better player.
Sure - you get that feeling from blunders too. But take a look at the Stockfish vs Alpha Zero games - Stockfish doesn't blunder. It it just outplayed: https://www.chess.com/news/view/updated-alphazero-crushes-st...
If you watch from here in game one you can see the "oh shit" moment, as Stockfish's evaluation drops from +1 to even to -1: https://youtu.be/Q5EPqM8gS7k?t=255