Unfortunately today I apparently made a similar mistake without realizing it. I had an query for casacorona about a continuation of what had been a really interesting topic at a panel at the Phoenix Westercon. After the Editor/Writer panel where she and jaylake had interviewed each other, I saw her in the hallway and walked up and said hi and broached the topic.
Add to the list: an editor walking down the hallway after a panel might already be doing business again. Or something, because her response was crisp enough that I knew quite clearly both that this conversation was highly unlikely to occur, and don't bother sending her any manuscripts. I had clearly crossed the wrong line.
I'm not entirely certain what I did wrong, but approaching editors outside of panels is definitely off the list of things I'll be doing in the future.