Sounds like you got a tough agent. I'm sure with the money the company is losing these days, there is all kinds of pressure to collect everything they can, but most agents will bend the rules on something like this, and do an "involuntary reroute", especially when it makes good common sense. Establishing a cut rate station (BWI) that close to a high yield location like DCA is senseless. They are so busy fighting off SWA (and probably losing money on every ticket), they have lost sight of the fact that you pick your fights where you can win them, and you don't cannibalize your traffic. It's a little like Ralph Lauren opening an outlet store in lower Manhattan, when the main store is 20 minutes away by subway. That would never happen...but this does.