There's two factual errors which Hiiragi-sensei made in this chapter:
1. The story about the religious man is apocryphal: the dish's modern name most likely comes from a particular opera singer and gourmand.
2. "Anchovy" is a false cognate with the Swedish "ansjovis," or pickled sprats, in several European languages, notably English. Due to the resulting mistranslation, it is very common for recipes to erroneously call for anchovies; they are very salty and have a wonderful flavour, yes, but one that differs greatly from the Swedish fish (although the resulting, different dish is apparently pretty good). In Sweden, they use sprats or, sometimes, herring for the dish; as such, anchovies are not the substitute to go for if you can't get your hands on some sprats. (Her information at the end of the chapter only gets some of this correct.)