Hi Sean,
I would make the following:
1. I'd make a HtmlHelper extension method, let's say
DivWithPermission(string innerHtml, string permission) with tag
rendering rules inside.
2. I would use a brand new Spark feature "Bindings" to create a
binding for <div> like this:
<element name="div">Html.DivWithPermission('child::*', '@permission')</
element>
After that it's possible to use permission attribute in your div in
Spark markup.
Warning! I've personally never tried this approach, so I don't know
the possible obstacles. But this way looks doable.