I recently read Robert Penner’s The Dark King Swallows the World, a novel set in Cornwall during World War II. I liked it a lot, and was surprised to learn that a few (of the otherwise uniformly positive) reviews had called it out for a lack of historical accuracy. 

My initial response was: who cares? Complaining about historical accuracy in a work of fiction seems, to me, like bragging about being the best at doing homework. Missing the point, a little obnoxious.