Assume that OOo Writer documents will be converted at some point to FrameMaker. This may be done for various reasons. One being that Writer is easier to learn than FrameMaker with its steep learning curve. So then an author may choose to write with OOo (or MSO), and an editor later will convert the documents to FrameMaker in order to produce some editing functions that Writer (or MSO) either cannot do at all or do well.
For example, OOo doesn't do run-in subheads with the ease and flexibility of FrameMaker, and Writer also doesn't do cross-references easily among separate documents (e.g., chapter subdocuments for a book, etc.) , whereas FrameMaker relatively excels in those two functions.
If the writer in OOo and the editor using FrameMaker were to use as much as possible the same style/tag names, there would be less confusion and ambiguity between writer and editor. If XML are also used, then the same DTD definitions should be used by both writer and editor, such as standard DocBook.
However, it is commonplace for writers in XML to use the head element instead of the DocBook standard title element--which perform the same function. In such case, the editor may choose to deviate from standard DocBook and change all of its DTD/EDD references from title to head, so that the writer could continue using head.
Having two slightly different DTDs/EDDs for such XML-structured authoring should not pose any problem for a knowledgeable editor. Having the editor make such changes instead of the author should reduce errors in communication/agreement because the editor is usually the more experienced of the two in XML template and application programming.