Is there a reason to not store the document in an abstract format that is more easily handled by systems useful for legal analysts (e.g. giving you the ability to diff text), and just “renders” to the accepted format? (I’m picturing storing the docs as LaTeX, but anything like that would work. Maybe there could be a legal “theme” for a markdown processor, for example.)
Because, in such cases, it wouldn’t really matter if the editor renders the source to text incorrectly, as long as the proofer renders it correctly. Just like with WYSIWYG desktop-publishing software.
Storage formats aren't the issue. We diff and merge documents just fine, and do render them in different formats in some uses cases for specific audiences. Nor is it about a final rendered document. It is the details of workflows and collaborations that happen before a document is ever finalized where the the editing and reading experiences must match.
Because, in such cases, it wouldn’t really matter if the editor renders the source to text incorrectly, as long as the proofer renders it correctly. Just like with WYSIWYG desktop-publishing software.