Let people deregister, I see no reason to force someone on the voter rolls against their will. A ban would be utterly pointless because deregistering does no harm to the game, the drama queens who rage quit because they lost an election are going to be drama queens, a dereg ban wouldn't solve that, it would just simply move their whining from the New Register Thread to its own dedicated thread.
And regarding the "What's wrong with just deleting campaign PMs?" point, I don't get why we should still go out of our way to inconvenience people with messages about a game they want nothing to do with. It's all just a hassle that could simply be solved by one post in the registration thread followed by two clicks on Peebs' mouse.
I agree with this, I'm not convinced that deregistration does any actual harm that creates a NEED to change the law. Let people do what they want.