I wonder about the skill level of the writer/typist.

   "Forty university students in their early twenties"

Most older people learned to write and only learned to type when access to typewriters and computers became common.

But these forty 20-year-olds? They were probably using keyboards since the beginning, and may have written maybe in grade school or for a signature.

Fluency using a keyboard can be quite easy on the brain. I've been typing a long time and I don't even think of the spelling or word, it just comes out on the screen. In fact, I have forgotten logins and passwords, but my fingers will dutifully type them anyway.

I can also write, but I gave it for keyboards, and now I'm quite rusty. My writing is less legible and requires more concentration.