According to the author, all it does is renames D3D executables to Crysis.exe and OpenGL ones to etqw.exe.
How does the author seriously expect this to be a robust solution? Not only will it stop application specific optimizations from working as required for the original application, it?ll also force invalid optimizations by renaming the executable.
You?re much better off using advanced Cat AI to try to force AFR; at least that won?t break application specific optimizations.