He could as well be either a demented pensioneer or a very clever troll/sockpuppet. We will never know for sure "the why" unless we break into the NSA.

While we decided to tolerate him, the best strategy is to simply minimise the damage. A warning for newbies is enough.

Feeding costs your nerves and that of others too. He already proved to be inaccessible to reason, so minimal unemotional replying is IMHO the best approach.

I have to admit I'm in an easy position because I'm blocking his posts from my view. So continue as you like, as long as you feel it's not diminishing your fun factor here.

I wouldn't like to see valuable contributers like you being frustrated. :)