> You can do the same thing with any screen by holding it the appropriate distance.

Exactly! Commented earlier: https://news.ycombinator.com/item?id=41862459

> Keep in mind that all that unwatchable area is pixels that aren't being used to improve the movie image.

Or maybe it's like the Philips Ambilight+Hue, that people swear adds immersion by letting content color the environment around it.