To be fair to Brendan, if an administrator requests by PM that a poster withdraw a comment (on the basis of defamation), and they first ignore the request, and then blatantly refuse to do so, the recourse normally would be to ban them surely? This is a complete breach of site etiquette (as well as being very rude to moderators/administrators who give a large amount of their time free, in moderating this site).If this had been made about any other named or identifiable individual, it would have been deleted and the poster warned for defamation. I simply asked him by PM to withdraw the comment, which he first ignored and then refused to do.
If someone wants to use this site, they need to abide by site rules/moderating decisions. This is what maintains the high quality of the site.