A computer screen hurts your eyes. You don't really feel it, it's subconscious.

That's why people don't read web pages, instead, they scan them for information, find what they need, and go.

I thought this was pretty well accepted - it is accepted in the Human Computer Interaction / Usability world at least.

I'm guessing this is a deeper dive into that phenomenon, and focused on cell phones vs computer screens?

It's one of the reasons I have a Kindle with the "e-ink" - it really reads like a book, not like a computer. It's wonderful for reading.