I see this all the time, that people cannot perceive pixels smaller than x degrees (using angular units to cancel out pixel size vs. view distance). And it's tr

I see this all the time, that people cannot perceive pixels smaller than x degrees (using angular units to cancel out pixel size vs. view distance). And it's true--the eye cannot resolve smaller that that value. But just as we cannot perceive individual frames at 24 Hz, but instead see motion, there's still an emergent effect that is perceived when we juice that frame rate up to 60, or 120, etc. There exists a frame rate where the perception changes from "really fast slideshow" to "motion" and that value is pretty low (something like 12 Hz?). Yet, higher frame rates still deliver a noticeable change in the quality of the video. I think the same effect will apply to very high pixel densities. Moire effects that occur when the news anchor is wearing a striped jacket, for example. There's gotta be other emergent qualities that come out of having such a tight pixel density, even if no single pixel can be discerned at a 3 meter distance. (Disclaimer: the above is pure conjecture, I have not compared a 4K display to an HD one from normal viewing distance)