What do you mean by transclusion workarounds?
Well, imagine you try to protect [[secret:WorldDomination]].
You couldn't directly access that site, because Apache would recognize
the URL.
However, you could still access the contents of that page by adding the
following to any non-restricted page: {{secret:WorldDomination}} - here
MW would simply pull the contents of that protected page from the
database and include it in the non-restricted page.
-- F.