[vouwfietsman]

> Book chapter numbers are ordinal numbers

> Book chapters and page numbers are not offsets.

I don't know but I feel like you are making a point out of something arbitrary. When I listen to an audio book, everyone always says: "Chapter 1", not "the first chapter" so why is this important?

I think extreme attention to to arbitrary meaningless details is how we ended up with most rules in language that we are starting to collectively detest.