On the 1250 miles DCA perimeter -- it used to be less - maybe 1100 miles. Then many years back they extended it to 1250 to allow non-stops to DFW and IAH. I think a politician from Texas got that extension.

But AA used to fly DCA-IAD-DFW to get around the rule.. I have flow this flight from DCA - but way back. It stopped at IAD for departures only, no arrivals allowed. That was when the mobile lounges took you directly to the plane (the way the airport was designed). So the stop was quick, and the mobile lounge was waiting with the passengers boarding at IAD. So no need to go to a gate. Well they did not have gates for the plane in those days at IAD. But I am sure they did some refueling at IAD.