As others have said, rolling hubs can be a good thing.

But you *do* have to have enough density, otherwise you get very long connection times. Even AA currently, with the rolling hub and the great DFW density has moderately long connection times. If you go much longer, you become vulnerable when talking about locations that have non-stop service by other carriers between them.

One thing I *like* about banks is that I don't pay a huge time penalty for connecting through a hub -- especially DTW, which is, without a doubt, the best hub on the planet for short connections, since you can get from gate to gate in no time at all...

Steve