Gotta say I don't know what was up with aircraft inspections at DFW yesterday (24th). The DFW-MIA 4.45pm got severely delayed because of some paperwork regarding inspections were not completed (the plane had been on the ground for hours at the gate!). The other MIA flight (6.15pm) also got similar problems and finally the flight I actually flew on AA963 got an hour delayed because of them forgetting to inspect it [started about 30 mins before scheduled departure!].
The rebookings AA handled excellent for passengers that wished to get off the delayed MIA flight, so no issues there. But I am usually impressed with how US airlines act during IRROPS - usually very easy to get rebooked according to your wishes if there are seats!