I see your point but
No need to make a somewhat new member feel unwelcome. I think there is a natural compulsion for anyone who posts a thread to want to see it grow into a large discussion. Sooner or later people just accept it if it becomes a dead thread.
I have to admit I don't read ALL of his (or anyone else's) posts, so maybe there was something that really bugged you that I didn't see, but PS seems to have a lot of passion for space science just like the rest of us. Give the guy a break.