That might be the published parameters but my experience has been a bit more inconsistent. While both EWR-IAH last flight and SEA-IAH midnight redeye got me the cold plate since Thanksgiving, flying IAH-SLC at 2100 2 months ago got me a bag of pop chips. FYI that is a 1195 mile route and block time is about 3:30 with actual gate to gate times running as little as 3:00 in my experience. (do note that the SLC-IAH 12:40 did have a real lunch meal, but no dessert unless there maybe was a brownie-thing I forgot about) As the DC area and SLC are about the same distance from IAH, I am not at all surprised that DC gets some inconsistency. As far as I can remember there was always a distinct difference from the 1200 mi range and the 1400+ range that covers NYC from IAH.