You didn’t notice, but it was there...I wish I didn’t notice but I do. Micro second micro-stutters. It’s no longer smooth as glass.iPad Pro 12.9 2017 didn’t have any stuttering on iOS 10.
While I do not have that specific device I do have the Pro 10.5. It’s benchmark scores are slightly higher than the 12.9 (identical hardware but slightly lower resolution). Just like the 7 Benchmarks slightly better than the 7+....and so on.
There’s a guy on this forum who claims his iPhone 4 on iOS 7 works great, clearly there is a wide range of expectations.
My expectations are not above what Apple has done, unfortunately they are higher than what Apple is doing.