Well, right off the top of my head, it would be cost-effective if you could reduce overnights. Second, it may not be about cost-effectiveness, but about providing a solution to a new problem. Again, if laws change to make it punitive to commute, then there is a problem which cannot be solved entirely on the backs of commuters, or the company. But that's speculation based on laws that haven't yet changed.

What I think the company would really be after is to create an alternative to massive shifts between North and South bases. Instead of having a senior North guy go to NYC, and a junior South guy be pushed off to DTW, why not give BOTH a new alternative? Why not, for example, take a little flying out of both, and create (I know some will soil themselves at this example)... a BOS base? I think anything that causes movement based on AE's is good for the company. So they reduce DTW a little, NYC a little, but anyone with the seniority can get in to BOS. Since the flying "moved" no backfill is needed in DTW or NYC. Take a little bit of the flying away from existing bases, and cover new bases, and you've probably taken care of many of the people who wanted to adjust their commuting pattern, and move into the opposite base. You actually shifted them to something better. All that's left are people who live in each other's pre-merger base, i.e. the South guy that lives in DTW, and the die-hards that have some other reason to need that particular base. I don't know if I'm explaining this well. Simply stated: I suspect that creating new options reduce the problem of cross-training, and moving expenses in between existing bases.

Again, none of this suits me very much, because I drive to a current base, but these are some of the motivations that I think are at play.