Dave, as far as I'm aware, Max does log the IP address of every post so he has a means of finding out who has posted what if he feels there is a need.The way I see it, the beauty of the Guest system is that it allows a "passer by" to create or contribute to a thread. The fact of the matter is that we do get many useful posts from Guests and I fear that much of this would be lost if they had to register with the site in any way.
I'm afraid I don't hold with the rest of the Guest arguement. Quite frankly if a person likes this site and wants to contribute on a regular basis, I believe they should join.
Perhaps there are issues concerning identity that need addressing but the information held in the membership database is not availible to everyone. There is a user option to make certain information availible to other members (which I don't know how to use) but that is a user choice. Other than that, the information is only avialable to Max and people trusted by Max to use that information in order to provide help here and it is not used for any other purpose.
Ultimately though, those who have been here a while and choose not to register, intentionally or otherwise are making one clear statement: "I do not trust Max". I can't help but wonder what these people are doing visiting his site.
Jon