Maybe it's either-or. Either you get 30% better performance, or you get 20% less power consumption. Kind of reminds me of how Android phones artificially speed up when known benchmarks are run.
Speaking of smartphone performance, it looks like Samsung is trying to push 4K video onto its devices. Wow, no wonder these chips overheat. Better not have that phone in your pocket when you stream 4K House of Cards onto your TV ...