In my country it is a saying that if you slap back a madman in return for having slapped you, people would make fun of you and not the other person as the other person is already mad and does not know what he is doing.
As such, it is best for me to stay away from arguing with this person. But yes, I will put in my post whenever I can if I realize someone is misguiding people at QL through his post as a part of his natural, inborn habit.