Hmm, building the general room descriptions and the like, you mean? Well, you got a point, that's very possible, however, I was talking about actually building the areas themself complete with thei scripts, programs or whatever you call them. Sure, you can plan them in, but you simply can't actually make them. Yet. Heck, you can't even be sure it would be possible to start with considering you don't know anything about the capabilities of a yet to be build codebase/mudengine.

Still, like you said, with a whole lot of imagination and determination you can still start with the room descriptions already...