Originally Posted by
saaveraward
Yeah, I just reviewed the thread and I see what you mean. From a practical point of view, the instructions are easy: if you are able to get your bag checked to the final destination, and you see two signs when you get off of the plane -- one for transfers and one for passengers terminating in Washington -- follow the sign for transfers.
But that isn't particularly useful information for advance planning.
I've done international to domestic at IAD, but only within *A, so I'm deferring to the experiences of others. Still, the main purpose of midfield clearance is to expedite connections for UA passengers, and I could easily see why that wouldn't be priority for non-*A airlines. I mean, if you're connecting from BA to AA or KE to DL or whatnot, taking a moon buggy over to the C terminal, and then going through security there, isn't particularly useful, since C/D is all-UA (and maybe AC?). You'd just have to hop on another moon buggy back.