What I'm doing here is merely thinking out loud. I too am aware that this is way too much work, as I mentioned above.
Think of the problem I'm trying to solve as the subroutine problem for web navigation. You're calling the permissions interface as a subroutine, and you want to maintain the call stack, i.e., you want to show the user how they got there (which implies, among other things, what they're setting permissions for), and how to get back. Permissions is not the only instance of this problem, I recall having the same thing in workflow, where I wanted to provide multiple interfaces for modifying the workflow net, but they'd all share the same "edit this transition", "edit this place" pages.
And while I was at it, I figured it'd be nice if the current context bar could be augmented with some state, so that when you navigate to a certain node in the site map, and then to a node below site map, when you click back to site map through the context bar, it'd remember where you'd surfed to.
So that's how it came about, and I'm merely trying to see if some simple, clean, easily implementable design idea comes out of it. None has so far.