How should OCX handle the styling of content?

[science]

Proposal: OCX should state as a goal that the content should be "clean" (usually clean HTML) but OCX won't require in the spec what the HTML (or other format) has in regard to internal styling.

OCX might provide a tag for "required user interface element" - so interface for navigation, bread crumbs and similar could be identified so consuming parties can know that they are there, and work on figuring out if they should be replaced for their purpose, or left in (but this signals that "if you take this UI out, the content doesn't work").