Ford thinks its nonsense.Or at least Ford thinks such things as efficiency, emissions, and utility need to occasional counterbalance--or he is what we read into the report from Mustangs Dailythat the Shelby GT500 Mustang will carry forward into the next generation of the car,due as a 2014 model sometime next year.While the Mustang line itself has gotten rather efficient, scoring up to 30 mpg high