The Tutorial Map runs horrible in portable mode, it's literally jumping all the time from 60 to 30 fps, making the game look way more laggy than it actually is. Who ever thought using double buffer vsync was a good idea needs to be fired. (Not literally but that's just how i see it.)
Zelda Breath of the Wild already showed us how bad and impractical double buffer vsync can be when you can't maintain the target frame rate 100% of the time. My only hope is, that they'll bring us triple buffered vsync with a future patch instead.
Performance can be cut nearly in half cases where every frame takes just a little longer than 16.67 ms (1/60th of a second). In such a case, frame rate would drop to 30 FPS despite the fact that the game should run at just under 60 FPS.