Standby tiebreak is check-in time, not request time, so make sure to check in for your ticketed flight right at T-24.

I haven't tried it myself, but apparently you can now request standby online.
http://www.aa.com/i18n/utility/sameDayTravel.jsp

You can also view the standby lists on the app. So check there when your meetings are done. If you're #1 or maybe #2, it's worth the early trip to the airport. If there are several names ahead of you, enjoy one last beignet or oyster instead and just head to the airport for your booked flight.