Originally Posted by Check Essential

Duke-
Lots of history in the answer to your question.
Short version -- it was done in the NWA bankruptcy under the threat of 1113 contract rejection.
Management was demanding more outsourced flying and the pilots were able to get some flow-through language in return. Management held all the cards at the time because they had a federal BK judge to help.
This is not a North/South thing at all. We all live under the same scope clause now.