Board Thread:Support Requests - Designing Your Wiki/@comment-1653025-20130410040238/@comment-3335785-20130410194340

Personally, I'd have blocked him infinitely long ago. 15 mins (the first block length) is not a punishment, it's a coffee break.

You have the right idea about increasing block length each time, but it goes more like 1 day -> 3 days -> 1 week -> 2 weeks -> 1 month/infinite. He clearly has no intention other than to disrupt the wiki, in which case I'd skip straight to infinite.