It was the only way I could get it all to work.  I tried nested resources, but using namespace kept pre-appending "dashboard" to all the paths in Scholarsphere.  Using scope fixed that, but I was unable to find a way to use nested resources within that scope, and preserving /dashboard/files to call the appropriate action in the my/files controller, and other controllers.

I will point out that this solution solves the integration issue I was having in Scholarsphere, while preserving all the existing behaviors and satisfying the testing requirements... all with fewer lines of code.