martin Hey Martin. I have an offer to go back but I'm not taking it just yet. I wouldn't want to go back to a screen intensive job without being completely confident that I could handle it. But if I did, the e-ink monitor would become an essential component of my work setup. Luckily, it's lighter than an iPad so you can take it pretty much anywhere. Not to mention that beyond the monitor function it was pretty much designed for document reading and editing!
As for polarisation, that's a very interesting point you've made. Since the iPhone 6 (edit: iPhone 5) apple has been using a quarter-wave polarisation technique to increase visibility in sunlight. When viewed through polarised sunnies the screen transitions from blue to pink. I wonder if, due to binocular perspective, different areas of the screen will produce slightly different polarisations even at one orientation. Additionally, I myself have been diagnosed with eye convergence issues (exophoria), which ties in to what you're saying. I suppose one way to test this is to wear an eye patch whilst using the phone to eliminate binocular strain. I can probably try this since, you know, I'm unemployed and all.
For iPhones we can eliminate PWM, but KM is right that we can't eliminate dithering because nobody knows for sure. As someone with access to research grade microscopes and high end slow motion cameras, I wonder if I could test for dithering on a pixel level? I recall once putting a friend's galaxy S7 under a thin section microscope and looking at each individual pixel's RBG cells. If I attached a slow motion camera, perhaps I would be able to detect colour changes of individual pixels either visibly or in software? Does anybody know if dithering would be evident enough to observe with a slow motion camera?
I genuinely think that research needs to be done on the eye strain that some people experience. Maybe with the iPhone X WM outcry there'll be more support!