On Nov 23, 2013 6:52 PM, "Eli Zaretskii" <eliz@gnu.org> wrote:
>

> >
> > Styles may depend on the structure to. Compare the spec for CSS.
>
> They may, but they don't need to.  I hope in Emacs they will not.

This is a must when you are designing web pages. So for compatibility reasons I think it would be unlucky if Emacs did not support this.

However I do not know how the standard text document formats look in this regard.