Ben and Sean,
After a bit more thought, I believe that it should be okay to make copies, but there does need to be a single primary repository where the correct and latest configuration can be found.
Putting copies of configurations into repositories to make project discovery easier is a good use of copies. Copies are also useful when creating mirror repos....
But one must be able to determine the location of the canonical repository for the configuration.��
If the configuration were always co-located with the packages then it would relatively easy to figure out where to find the newest and 'correctest' configuration.��
The canonical location should ALWAYS be used in project references.
Dale