On the basis of this post,
http://www.flyertalk.com/forum/showt...72#post9525272, 2 hours flight time and the IATA's Jet A index for 5/16/08, it costs $12.57 more per seat to fly an MD-80 DFW-ORD than it would a 737-800. That can clearly be worth it in terms of schedule frequency for business travelers.
By that same math, it means that the
total fuel cost per seat for that MD-80 is only $52.14. With an average load factor of 75%, that should work out pretty well with average fares.
Some people take every opportunity to dump on MD-80s regardless of the math.
I don't know how AA maintains service to all cities with 12% service cuts, especially when major hubs look to be set for no reduction, but I know better than to argue routes with MAH4546.