I'm with the OP here too. My bet is that the FAM wanted your seat, and rather than bump someone else in first so you can take their seat, they just bumped you. 21% less work, I guess. I've purchased a few of those fares in my time (mostly on AA), and my travel agent shows them as FIRST CLASS on my confirmation with no mention of coach. Only on asking them they tell me its officially a coach ticket upgraded at ticketing at no charge.
I would think that USAirways would offer that special cert that lets you upgrade any flight in advance (I forget what its called) to make up for what happened; in theory that upgrade doesn't cost them much or anything, and is fair. But oh well, I guess we can't expect much from "Your Fault"