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I think that the merger is a fait accompli, but that all the doom and gloom associated with it that you've cited is a mix of reality and over-reaching. Losing the 733/735s isn't a bad thing, for starters. They're old and have small F cabins. Seeing IAH shrink would be surprising, though it would not be the end of the world, especially if fewer E/W connections are routed through it and its role as a connector to S. America and Latin America is increased. There are a lot of questions surrounding any merger, and most of the things you identified will be covered in them.