right, and fglrx is just awesome now....
Well, actually they didn't rewrite their whole codebase. It was "just" the 3d part and one more low-level thing in order to improve performance and add AIGLX support. The part was (well, at least mostly) completely independant from any future Crossfire support, so it would have been the same mess anyways.
By the way, the driver was buggy enough with 8.42, I don't even want to imagine how buggy it would've been if they even had Crossfire implemented at that time.