The problem here will be in implementing and SW passenger mentality. Say the flight is 1/3rd empty and a WGA passenger got an assigned middle seat at the back. Once he notices flight is 1/3rd empty and there are open seats upfront , what stopping him from sitting in any of those ? Especially because SWA had open seating before ? The mentality will still be there. I can see a flood of people trying to take those open seats after boarding ? Not sure how SWA plans to go about this.