Editing on Paper

I read Nicholas Carr's book The Shallows: What the Internet is Doing to Our Brains and have a number of questions about it to bring up here. The thesis is that on-line activity causes alterations in brain structure that limits our ability to read deeply for long periods of time, an ability that developed originally because of our interactions with books. I don't want to talk about the thesis itself today, but something he uses to motivate the notion. He speaks of not being able to edit on the computer, but having to print work out and edit on paper and then go back and make changes. He wonders whether those who will be brought up on screens will have the same preference, thinking the answer will be no.

I, too, always edit on paper. Is this common? Do those of your in college or grad school edit on screen or on paper? Is there, in fact, a generational split here?