Originally Posted by
Globaliser
One other thing to remember is that (if I've understood you correctly) you're potentially buying two different things. One is an award ticket using US Airways miles in accordance with the US Airways scheme. The other is an award ticket using Avios in accordance with the British Airways scheme. It isn't surprising that the two schemes may price these tickets differently, both in the number of miles/points/Avios required and also in relation to the cash element.
Yes, I realize they are two different things... I just think I read somewhere that BA only pass on whatever fees US Airways charge. I guess I misunderstood what that means.