Why talk JATS documentation?

To be honest, I am talking about JATS because it is the documentation I know best for the tag set I know well. But there are good reasons to examine what has been done with JATS. People have stated (in public at conferences) that the reason JATS has been so successful is its documentation. The documentation far exceeds that of the immediate predecessors to JATS; AAP DTD and ISO-12083.

My other rationale for this paper is that I would like feedback from this community, concerning how the JATS documentation can be improved. Most conference attendees have worked with many tag sets, most of them non-JATS. What can these communities learn form each other?