Interesting. Apart from the wrist issue, the strain of constantly moving one’s eyes from keyboard to screen and back is really underestimated IMO. To be able to keep your eyes fixed on one place while typing is a serious luxury. I sometimes think that learning to touch-type when I was 17 was the single most useful thing I have ever done. It took a week. And then, as I remember, just a few months to overtake my former typing speed.