I only banned him while I was waiting for a reply to the email I sent him. In fact I thought I'd already unbanned him, though I noticed just now that he was still banned. What a tempest in a teapot.
Incidentally, this post and its predecessors illustrate perfectly why the site guidelines ask users to contact us about problems with moderation rather than posting on the site about them. Though nearly empty of content, they get upvoted faster than anything else.