I think you and others are not clearly understanding what goes on to make a game. Like I have said previous, someone at AMD "should" be ripping the GameWorks libraries to pieces and seeing what makes it tick (The very same thing that Nvidia will be doing with Mantle). Once they have done this, they will be able to implement optimizations for AMD hardware.
Because GameWorks is brand new, this isn't going to happen over night but these optimizations will be implimented from AMD devs in the game code and driver level. It isn't that hard to understand but people seem to miss this?
GameWorks is a closed Library Greg. Its not going to be ripped to pieces by devs or AMD. Nvidia are the ones responsible for it all. Only they can provide optimizations.
I urge you to take a read of the comments here. The author of the article explains the score to a couple of people posing questions at the bottom.
http://www.extremetech.com/extreme/...surps-power-from-developers-end-users-and-amd