Yes, if at least your GPU will move to red camp, and the API gets widely adopted by game devs... or Nvidia will be able to adopt Mantle in the next GPU generation...
I expect lower percentual increase as the CPU (and maybe memory overclock) is intended to remove/decrease effect of CPU overhead. The other scenario is that percentual increases will remain the same as total performance will increase.
Then considering this approach, you can archeive better results and GPU utilization with less watts for CPU... Just remember that AMD made some tests on underclocked FX 8350. More threads, lower frequency... At all seems promising.
Edited by Offler - 1/30/14 at 12:59am