The reason they are often “perfect” under X is that you are quite likely to be using a compositor which adds the exact same latency, if not more (due to then Xs

The reason they are often “perfect” under X is that you are quite likely to be using a compositor which adds the exact same latency, if not more (due to then Xserver itself being a useless middlemen only). Did you try viewing a full screen video on X without a compositor? Even though today’s video hardware is indeed fast enough to mask it more often than not, display technology also requires more and more resources — I am sure you will find plenty of tearing at larger than 1080p resolution and higher framerate. And come on, how is it extreme amounts of coordination? That’s like the most basic coordination there is. Especially that it can be circumvented in the rare case it is not needed — e.g. game windows in full screen can render at their heart’s content.