There are some hardline old schoolers who claim the whole protocol is 'just something wannabe people do online' - since most online interaction is written it makes sense that this is where such a protocol would develop. Though, I am sure it was something used even before the internet on the occasions when a sub and Dom/me communicated by letter.

Hopper - sounds like the chatroom you mention above supports the theory of the old schoolers. Also looks like most people on this site have a relaxed attitude to the whole thing (I say most because I am sure there are those who don't agree and who have simply not posted).