Why not? I have this in an otherwise-valid HTML5 + SVG 1.1 + MathML 2.0 + RDFa Lite 1.1 document:
<hgroup> <h1>Company Name</h1> <h2 role="presentation">Tagline</h2> </hgroup> Spec says: > Authors must not set the ARIA role and aria-* attributes in a manner that > conflicts with the > semantics described in the following table, except that the presentation role > may always be used.
