It wouldn't be surprise if Samsung is cheating in benchmarks again. Yes,
cheating! It's nothing new to them. They have done it before.
http://www.anandtech.com/show/7384/state-of-cheating-in-android-benchmarks
1) On the Exynos 5410, Samsung was detecting the presence of certain benchmarks and raising thermal limits (and thus max GPU frequency) in order to gain an edge on those benchmarks, and
2) On both Snapdragon 600 and Exynos 5410 SGS4 platforms, Samsung was detecting the presence of certain benchmarks and automatically driving CPU voltage/frequency to their highest state right away. Also on Snapdragon platforms, all cores are plugged in immediately upon benchmark detect.