> Seriously, please don't use C0 (except for LF and, I cede grudgingly, HT) and C1 characters in your plain text files.

It is (or, at least, used to be) common to have FF characters on plain text files, as a signal for your (dot matrix) printer to advance to the next page. So I'd add at least FF to that list.

I think we can deprecate dot printer specific advice wrt what we consider plain text today