I have generally had good luck through there, maybe every couple of months for the past two years. Usually I use the kiosk when I get off the train. Never had more than a 10 minute wait when I did need to see a ticket agent, but never in/out there on major holidays though.

When the first class agent cleared that line they would call for the next in the standard line. I have even shuttle over from IAD when flights were shut down there and got on the next plane out with NO charge. I actually prefer DCA if I can use it over IAD or BWI.