Never thought about it that way, but I agree with your thinking. Besides having to amortize the costs of the purchases, I would assume that the cost to operate those flights—whether by the original carriers or AA—were still higher than those of Southwest. AA more than UA or DL has a history of thinking that hub networks are the magic potion to profits—just look at how unsuccessful they’ve been with their hubs at SEA, SJC, STL, SJU, BNA, RDU, and JFK over the years. And ORD keeps shrinking compared to UA.