
A computer scientist specializes in the theory of computation and the design of computational systems. This book has great lessons turning newbies into computer prodigies in time.
He recommended "The Psychology of Human-Computer Interaction" (Card, Moran, et al) From that point forward, all roads led from Fitt's Law.
I mean, that was what the vi fans I met in my youth tried to deny. They claimed positioning by incremental search was better.
In a late uncle's stuff, I came across a copy of "The psychology of human computer interaction" by Stuart K. Card et al. A book from the early eighties detailing Xerox PARC UI research. They did a study comparing cursor keys (or vi keys), word and line keys (home, end, next word etc.), incremental search and mousing. They found the same as Apple later would.