- Edited
Link In my mind it's not about brightness wrt to dithering..its about movement. Watch @degen's videos. You can see movement everywhere because the E-ink panel makes it visible unlike an LCD. If you were reading a book where the white backround and black letters were always moving a little bit and changing shades even a little etc it would be tiring and hard to focus on. I think this is what dithering is like for us but on a much larger scale since even what looks like a solid white background is really a bunch of wiggly points rather than a solid area. Compound that with fonts, images, video etc its constant movement and that's exhausting for the eyes. All that wiggling, movement, changing of colors etc are not obvious to the naked eye but are straining the visual system nonetheless. It's like "seeing" a solid white paper and when zooming in realizing its thousands of maggots crawling all over each other. We may not recognize that movement when zoomed out, but the eye muscles and brain do and are filtering it. We are already filtering out so much when looking at LCDs on a macro scale that this might just be the straw breaking the camel's back.
Obviously this is entirely speculation, the dithering IS there but it might not bother us at all...or it might be the root cause and all the other stuff like PWM/eye accomodation etc are just additive factors or triggered by it. People were positive PWM was the root cause as well. But we need to rule this out if nothing else and there isn't any other obvious theory that at present doens't have a definitive way to test.