- "The computer writers took half as much time to write the first draft than pen and paper writers" (2).
- "The computer writers had a more fragmented writing process than the pen and paper writers" (3).
In other words, a first draft on the computer is edited more than the one on paper. Whether that means it is more polished is, of course, a different story.
In any case, I think such studies are more useful for studying handwriting versus keyboarding than the anecdotal evidence provided by writers themselves—no matter how famous.