Discussing rich text capabilities in a CMS is an exercise in compromise. Authors want the flexibility to be creative in their content. Developers want to ensure said content fits in the box. This can feel like fighting over the bed covers with a spouse: everyone initially means well, but things turn sour and we all wish for a bigger duvet. Or a more understanding spouse.
I believe the fundamental problem is one of control – for end users, control over content formatting, and predictability of the overall system. And for developers, control over content processing and rendering. Let’s crack open the rich text black box, and give everyone their fair share of the duvet.