http://techreport.com/news/26521/nvidia-responds-to-amd-gameworks-allegations
So, if GameWorks isn't the problem, then why do certain Nvidia-backed titles (such as Assassin's Creed IV: Black Flag, Arkham Asylum, and Watch Dogs) perform so comparatively poorly on AMD hardware? Nvidia's PR team butted in there, hinting that AMD's developer relations efforts are thinly spread. Considering AMD's ongoing financial hurdles, that's not outside the realm of possibility.