Michael E. Levine, a pioneer of airline deregulation, had a few very interesting obiter dicta in a talk he gave the other day to Washington's International Aviation Club. He suggested a segregation, a bifurcation as it were, of air travel between leisure travel and business-oriented travel may emerge from the US crisis - as is the case in Europe, with two networks coexisting. Levine asked more questions than he answered because (a) he knows he doesn't have the answers, and (b) that's what economists do, anyway. You can read his speech by going to the Club's website.
But here are some fascinating bits: Now, though, "as prices go up, price-sensitive travelers are leaving the system. Flights are consolidated into larger aircraft to get CASM down to where RASM has a prayer of covering it. As aircraft size rises and total passenger volume falls, the system shrinks. As the system shrinks, it become less attractive to convenience-oriented travelers and they resist paying more for less....Where will it end? ...Will leisure transportation continue to be produced jointly with business transportation?"