Two recent examples in the last 10 days of how poorly AA does on handling delays.
2/17 - VPS-DFW. Notice that inbound plane from DFW is leaving late, going through typical rolling delay. Eventually arrival time is pushed back to after proposed departure time for return, but no change from "on time" departure. Finally after scheduled arrival time is move back another hour, AA updates me that my flight is delayed which allows me to rebook through CLT.
2/23 ORD-DCA - 6:30pm get notice that 7:24pm departure is delayed until 8:00, no announcement from GA. 7:25 (boarding time for delayed 8:00 departure) agent makes first announcement of any kind and announces that we are waiting for a part from hanger, will board once part is installed. 7:45 or so, flight delayed until 8:15 no announcement. 8:00 or so, flight delayed until 8:35, no GA announcement. 8:30 (5 minutes from delayed departure time), GA makes second announcement and tells us part has been installed and we will board shortly. 8:35 - start boarding. While boarding departure time change to 9:05, we depart around 8:55. For extra fun, the upgrade list was 10+ deep, no upgrades clear and First Class goes out with 5 empty seats.