In order to accommodate this fictitious persnickety person I check and recheck the weather, the days of the week, the clothes, the food, the gossip. Was the 27th of March 1668 a Thursday? Was it a leap year? I should mention at this point that math is not my strong suit.
But getting it historically right is not just a move to avoid persnickety person censure. It is addictive. A non concrete fact will niggle and wiggle and insist on resolving into certainty. It will eventually drive me bonkers and get me up in the middle of the night to plow through whatever 17th century text is required, get out my calculator, realize it was actually a Tuesday and fix it.
This is exactly what happened with buttons. When did buttons come into common usage? Aristocrats were sewn into their clothes by their armies of staff. Great, but what about a candlemaker's daughter who had no staff? Was she busy sewing herself into her clothes? Improbable. Information about working class people is invariably harder to verify than their wealthier counterparts. Only lovely expensive clothes get preserved in museums. No one enshrines worn out working boots. People save their best things, not the things they use everyday. Frustrating. As it is also easier to take in clothing than to let it out, the clothes that get saved tend to be tiny as they can no longer be taken in any more. Were these people that small?
Getting it right is fun but at times impossible and I can only hope that the persnickety person will have some patience.