While this is true in theory, I don't know if it's been established in fact. There's some sort of rumor/myth/legend that Southwest's open seating is most effici

While this is true in theory, I don't know if it's been established in fact. There's some sort of rumor/myth/legend that Southwest's open seating is most efficient in practice, but I can't see any data to support this claim, and I'm dubious of it. The models don't cleanly capture things like breaking up families, adding confusion, etc. Southwest also has an interesting incentive structure where you're rewarded for being on time and getting into position with a better seat. While on other airlines, your incentive is the other way, where you'd prefer to stay off the plane as long as possible. I don't know the net practical effect.