If you click on the name at the top of a post you get a complete collection of links to all the posts they have made in any name when they have been logged in as members.
When people post as GUESTS with a name, clucking in that just gives all the posts they have made in that name. (When they don't use a name of course you just get a complete collection of all the nameless GUEST posts by all the nameless GUEST posters.)
This isn't the same as an organised collection of course, which would be a much more complicated thing to produce, and could be pretty interesting.
Someday there'll probably be PhD students doing research on the MUDCAT, I reckon. When we're all dead.