Great points - also, reading between the lines of his tweets, it sounds like the bug was pushed by a team he doesn't lead, so the best he can do is ask them "Please fix this, people are really pissed (at my team) because of this". But to the Image Search team, it's like, why should they do a costly rollback? It's easier for them to just sit back and say nothing, and let AMP soak up the blame on HN. Then they can fix the bug on their normal schedule, without their deadlines being affected.