I respect you as a moderator and I think that on the whole, you do a good job - but ultimately, the YC logo is up there on the top left of every HN page. You have earned the presumption of goodwill in almost all of your moderation actions, but when incentives favor YC, you need to (and will always need to) go out of your way to prove that you're addressing these issues without bias.
I saw your comment earlier about this particular case - the flamewar detector went off. This would be a good thing to bubble up somewhere for transparency. I've mentioned many times that a public moderation log for HN would be a very good idea, and it would avoid scenarios like this entirely.
Again, I have a lot of respect for you as a moderator, but that is dependent on being able to push back when HN moderation fails. I've gone to bat for you before; it's only fair that I get to criticise you, too. Maybe this was a bit of a low blow, and I apologise for that, but it highlights places where HN moderation can be improved all the same. I don't think that pushing to have all of these discussions in private is going to be acceptable.