Tony, thanks for your comments!
I’ve definitely spent the past several years in the Drupal world, but I don’t think the narrative-structure challenge (or the approaches I’m discussing) are in any way specific to one CMS or a particular programming language. You’re correct in that many different CMS platforms have arrived at similar conclusions… and yet, on project after project we find clients who’ve been left with a body field, a WYSIWYG editor, and a pile of HTML-insertion buttons.
The challenge isn’t simply technical, since the tools to build intelligent, modular content have been around for decades. The biggest hurdle is getting CMS integrators, web developers, and designers on the same page when it comes to the meaning of the underlying content they’re storing, manipulating, and presenting. XML and DITA are important not because they’re perfect technical solutions, but because their communities have learned to articulate many challenging questions about content structure.
I agree wholeheartedly that presenting raw markup to users isn’t the answer, and I hope that the space constraints of the article didn’t leave anyone with the wrong impression. Precise, meaningful markup (the kind that vanilla HTML can’t currently provide) is a critical foundation for the easy-to-use widgets and editing interfaces you describe. While it can simplify the markup jumble, it’s not the end of the process.