Sister Victoria, in 1987, had special powers. She was the typing teacher and we used "electric typewriters." Of all the typing that went on in the class, not only could she hear when someone used the "correction" key and who did it, she could actually hear when you started a new sentence without double popping the space bar.
I swear it amazed me. She would call the student by name from her desk as we did timed practice assignments for grades. "Johnny, two spaces after the sentence! Beth, no corrections! Accuracy is part of the assignment."
So she was wrong and I've been doing this wrongly for 15 years?
She wasn’t wrong. When we used typewriters with fixed fonts, two spaces was the norm. It was only with the advent of proportional spaced fonts and desktop publishing that one space became standard.