TIL my grandmother's bread recipe relied on a typo from 1928

I was going through my grandma's old recipe box last weekend and found her famous white bread recipe, the one everyone in the family raves about. The card said to add 1/4 cup of vinegar, which always seemed odd to me, but I never questioned it because the bread always turned out perfect. Out of curiosity I looked up the original cookbook it came from, a 1928 Farm Journal edition my aunt still owns, and the actual recipe calls for 1/4 teaspoon of vinegar. Somewhere along the line someone copied it wrong and my grandma just went with it for 50 years, and the extra acid actually made the dough rise slower but gave it that tangy crumb everyone loved. I tried making it both ways this week, and honestly the typo version is better, so I am keeping it as is. Has anyone else found a mistake in a family recipe that accidentally became the secret to the dish?