Would you consider adding that general advice to the official guidelines? The problem with "Don't say things you wouldn't say in a face to face conversation." is that there are plenty of people in life (maybe just in hacker circles, but my sample is thoroughly biased) who would say outrageous things that they would start with a disclaimer in a face to face conversation.
Actually I feel one of the benefits of the internet is that one can say things that wouldn't go down well in a face-to-face conversation. Not everything that makes sense is easy to accept.
