JDiver

What costs the airline more, having the SLF truck its own carry-on, or check it and have the paid employees in the airports and airside handle baggage? Where would they delineate the limit between a hefty "personal item" and carryon luggage? How would they enforce it, how many employees would it take, and how much delay and ill-will would it create? How effectively are they managing carryon luggage now and how are pax perceiving it?

Not to mention AA is still differentiating itself significantly - as are most legacy carriers - from the LCCs, an particularly from the hoi polloi pay-for-everything a la Ryanair approach.