Interesting thing is, living in Europe, AFAIR I never heard about "use two spaces" rule until now (even if in a long monospace plaintext, I might have subconsciously used it sometimes to disambiguate). If I saw that in a Word document, however, I would have thought the author was a technically-illiterate person who puts extra spaces around commas, quotes, parentheses etc. or uses 10 spaces instead of 1 tab for indent…
[1] https://en.wikipedia.org/wiki/Plenken [2] https://de.wikipedia.org/wiki/Leerzeichen_in_Komposita