One thing I've noticed in doing proofing runs, is that if I say, change the platform, affecting the size, spacing and font, I find all kinds of errors I would have missed prior. And what I mean by changing the platform, is downloading the draft ebook file for review which I can do on an ebook reader. But the same applies if I simply change the font and size in my Word document.
One of the advantages of having a paper copy to edit of course is you can carry it with you, so if you have some downtime, you can read through it and start reviewing. But your phone or tablet can offer the same portability.
I know, some people need the paper copies. I used to be that individual. I'm fairly old school and up until the late nineties the computer was just a better typewriter that you didn't have to spend a little money in ribbon and a lot of money in correction tape. Now, I can't bring myself to go back to those days. Even if I read through a printed copy, I would only highlight areas that needed attention later, or, I would sit down side by side with the computer and just hash through the edits as I go.
When I started engineering as a career, although CAD was not in its infancy, PDF's weren't a thing and you plotted full D sized sheets so you could mark them up and hand them back to your drafters. Today, we have large format paper roll plotters, which were the state of the art 20 years ago, sitting there unused. They sit there unused because it is easier, and more productive to review and edit with comments electronically, with the ability to zoom in where you need, than it is to have your drafter print you out a set, you mark it up in pen, package it up, get it back to your engineer or drafter, and the process repeats hopefully no more than three times, and it's usually days between iterations. Now, email, bam bam bam, return, a few hours later another set, a few more edits, and you cut the time in a fraction of what it would have otherwise been for the same level of quality and detail.