I'm just curious what gives with the speeds you guys are flying at cruise? Mach .74 or .75 in an Airbus? Twice now coming into JFK ATC asked you guys to speed up and the pilots said no. They were then given a 90 degree turn and descended 2000 ft so we could get by. It would seem to me that the turn and descent cost you guys a lot more fuel then just speeding up to .78 or .79 for the last 200 miles of the flight.