If you already know how to touch type, how do you know if you should train some more so you can type faster?
The author types at 120 wpm, so that's probably what he recommends. He doesn't say how much work it took him to get there from 60, but it was a conscious decision and special effort. On later occasion, he learned numbers.
Although he clearly advocates such speed, he doesn't really argue for it. What motivated him to speed up was text chat. What struck me as a good argument is that lots of people say that they are limited by what they have to say, not typing speed, but being able to type more gives the option of writing different things, such as more back-and-forth on message boards. If that's actually useful. But I didn't take his advice and still only type at 60wpm.
Previous open thread
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
Notes for future OT posters:
1. Please add the 'open_thread' tag.
2. Check if there is an active Open Thread before posting a new one.
3. Open Threads should be posted in Discussion, and not Main.
4. Open Threads should start on Monday, and end on Sunday.