This is a UI issue. It's not controversial. The mechanism is controversial. We are only leaving in the error codes, not the mechanism. Now in I-D directories.
Organizations like to keep their auth-ids secret.
Maybe we want to allow it. It's not intended to allow that. Need to clarify. Not sure how useful it is, but it should be there for completeness. If a group is removed, it's needed to know which groups to clean up.