Forget regret, or life is yours to miss.
~ Jonathan Larson (February 04, 1960 - January 25, 1996)
I think it'd be a nonstarter, ... The size of those two airlines, as well as overlap, makes it prohibitive to (the Department of) Justice. And you wouldn't have a clear leader in terms of the merger. Other deals being discussed, you know who's the buyer. With American and Delta, there would be more fighting.