Domain elements in map metadata

So I was poking around in content models of various map metadata elements (some bookmap, some both map and bookmap.) One thing I noticed is that they are somewhat inconsistent in what domain elements they allow inside. E.g. some of them include the highlighting domain (e.g. <organizationname>), and some of them do not (<author>). Other times I think I saw that not all of a domain was included.

Why the inconsistency? I'm guessing it's mostly the way things have evolved incrementally over the spec versions. But I wonder if this is an area that could do with some cleanup for 2.0.

As I got to pondering this, I couldn't help but also wonder why some of the domains are included in these sorts of things at all. E.g. the markup and XML mention domains seem to be included in pretty much everything I looked at. Do all of these metadata elements need those domain? Do any? Is the general philosophy just to be broadly inclusive, and restrict when appropriate? If so, has proper thought been given to all the restrictions that would be appropriate?

mag

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