I met Doug Englebart some years ago. Doug invented the mouse and developed it as a system for rapid execution of commands. In Doug's system, there were two parts, the mouse, which only moved the pointer, and a chording keyboard that you used to create commands using all five fingers. Apparently you could go very very fast with that system (it was part of his larger "Augment" project).

Apple saw that and reduced it to just a pointer and one button.

Now, almost 20 years later they're adding in the part Doug had at the start.

Hmmm...