Answer: It's the Houston Way.
Updated: We have a drive-time answer:
United says expanding Hobby would cost jobs, hurt economy, Chris Moran & Kiah Collier, Chron.com
Expanding Hobby Airport to allow for international flights will cost the Houston area 3,700 jobs and $295 million in economic activity, according to a study released by United Airlines Thursday afternoon. United's conclusions contrast starkly with the projections of a study commissioned by the Houston Airport System that an international Hobby would create 10,000 jobs and inject $1.6 billion into the local economy annually.The study was conducted by Barton Smith, an economy professor at the University of Houston and one of the more respected authorities in the Houston area. Now, granted, I'm certain he worked with data supplied by United, in addition to other data, so it's no surprise that this data had a United slant. It also probably solely focused on the effects to Jobs AT IAH, leaving out whatever job creation would occur at HOU so there's that. However, I would imagine that the net effect of jobs (throwing out the ridiculous numbers cited in the HAS study) would a loss for Houston should this go through.
I've always thought that the idea of creating a 2nd exclusionary hub for Southwest would be a bad idea. I see a (admittedly long-shot) way where this could work where different airlines were brought in to Hobby for some routes provided they also competed at IAH (and filled the empty gates there)* but that idea was never on the table.
What is on the table is a sure loser IMO. Perhaps there's some benefit to having a neutral third-party commission a survey to make sure, but I doubt it's even going to get that far. Houston is determined to NEVER be slighted by anyone, and many view that United slighted them by "moving" to Chicago**. To quote Kirk Russell: "Son of a bitch must pay."
*The plan I envisioned was much more involved than that. I was going to go into it one day, but since it's never going to happen I'm just going to let it lie.
**Of course, United never really "moved" to Chicago, they've always been based there and had a financial incentive to stay there. People who use this argument are arguing from a position of ignorance.