Writing peeve of the day.
Self-proclaimed typography experts who state – as if it was handed down on stone tablets from G-d – that you can only put one space after the period at the end of a sentence.
On a computer. Most likely in the context of html. Which, unless you insert special space-like objects (like , and if someone ends their sentences with . you should probably back slowly away because they know exactly what they’re doing and it’s not writing (hint: 8 letters, starts with t, lives under a bridge and goes fishing)), treats text as a compressible fluid that serves to separate items and which is typically squashed down to an ~1em wide void.
Look, it’s lovely that you’re doing all your composition on a typewriter, then scanning it in with some bespoke OCR software inside a vmware’d Windows 3.1 environment, and that if you accidentally put a second space after a period the OCR software will dump core and bring the entire virtual machine down with it, but that’s not how everybody does it. I use software that lets me feed regular old text into the computer and end up with nicely typeset pages with, shockingly, automatically set spacing between sentences. And it doesn’t matter if I put one space after the period. Or if I put five. Or twenty.
How about, just as a bit of friendly advice, that you upgrade your publishing dataflow so it doesn’t involve a linotype? If you actually use a computer, wonderful things will happen without having to worry about counting how many effing spaces come after the end of the sentence.