It means that he had two responses to one post directed to neither of you - one of those responses being a rather rude rhetorical question asking him if he is able to read by the Private Leader of these boards.
So it probably means to keep his chin up and to keep directing his posts to who they are intended for, especially since it is Jess and she is always very respectful.
Because I don't know about you, but I would feel extremely disheartened being new to the boards and having the Private Leader ask me if I am illiterate.
Well I'm pretty sure when you post on a public forum anyone can respond to it whether you're specifically talking to them or not. Don't act like you've never responded to a post that wasn't directed at you before. The point is this conversation has been going on for a while now and it's annoying to watch a person jump in when they clearly haven't educated themselves on the current trajectory of said conversation.