If you bothered to watch the video, it was about 3d touch menus and simply exiting out of settings. The drop in frame rate activating 3D touch in the video is the same sort of frame-rate drop I get in my Mini 2 in so many animations, which funnily enough goes away when transparency is turned off (As demonstrated in that video). Then there are the random stutters all the time, which happened in that video when the home button was pressed while in settings.
I think it is ridiculous that Apple can't put together a mobile OS that can't just render animations and blurs well, especially when that OS was minimal on featured and was specifically meant to improve animations, speed and stability.
I think its also pretty bad that the Air 2 will lag and stutter when moving between apps in split screen mode and in 10 minutes of playing with an iPad Pro, there was the occasional stuttering. Its pretty hilarious with the overkill specs that the iPad Pro has and the powerful specs that the Air 2 have, that iOS 9 still doesn't fully cope. That is truly a sign of some poor coding or optimisation.
My $90 Windows tablet is cheap and quite underpowered, yet it can consistantly render animations, but for some reason iPads over $700 can't.
I guess though, there is no point in replying to this thread. I'll get called an Apple hater, because I don't consider stutter and lag on expensive high end products reasonable or normal.