There's definitely more going on than meets the eye. As embarrassing as I may sound, I take that part back about not being able to crash jj2+. I've just witnessed some hacking going on on TSF (like ppl being able to chat as Console and some other hacks). While trying to blend into the group, I decided to display a few uncommon haxes. It turned out that an old weapon hax program of mine can easily crash plus servers. Although I'm not sure how, it is definitely possible to crash plus servers.

EDIT: Seems like only some servers are vulnerable.