There is only a single way in which a required DIV element in |type="XHTML"| would be useful. It would only be useful if the XHTML namespace was defined directly on the DIV element, like:
<atom:entry> <div xmlns="http://www.w3.org/1999/xhtml";> ... </div> </atom:entry>
The DIV element would obviously not be considered part of the content and all the elements inside the DIV element should inherit the XHTML namespace and should not have a namespace prefix.
Than it would be possible to easy copy and paste and easily generate it from string-generators, like MovableType and WordPress.
However, this would seriously limit |type="XHTML"| and would require the Atom specification to define the DTD for the allowed XHTML elements. Since you can use MathML and SVG in a valid way inside the DIV element as well, with the proper DTD. For some people that is quite normal[1].
IMHO it would be better if your system can not guarentee to generate well-formed XHTML it would use |type="HTML"|. That is also interoperable and can be easily copy and pasted. I think we should recommend that to publishers instead of limiting |type="XHTML"|.
However, if we do want to limit |type="XHTML"| in this way we should do in a way that makes it useful. By defining the DTD and the exact way the namespace declarations should happen.
[1]<http://golem.ph.utexas.edu/~distler/blog/>
-- Anne van Kesteren <http://annevankesteren.nl/>
