Correcting by stamping white ink over a letter was indeed a marvelous improvement, but nothing like what came later with a word processor. Later word processors, like the Wang in the late 70's, destroyed Selectrics, and obsoleted the job of "secretary".

I remember my Mom typing his thesis over and over on the Royal typewriter. What a boring, dehumanizing task that was.

My dad abandoned his typewriter when he bought a Trash-80. I abandoned my typewriter when I discovered the printer in the computer center at Caltech around 1975. I'd use runoff, a marvelous program that is a precursor to HTML.