Tim-
As far as I've seen, this calculus thing is the first real argument he's gotten into, and that was settled quickly and reasonably. PP backed down. And making lots of minor edits, thereby wasting disk space, is not on our list of bannable offences at this time.
As I said previously, if a banned user returns while still under his ban, it should take relatively little or nothing for that ban to be enforced. But since several people have come out in defense of Lir, I'll wait with doing so.
Regards,
Erik