presumably only someone born in ben zimmer can consider to be ancient history it seems everyone has lost interest here but i made an effort to make some sense of this the article was confusing entirely separate uses of the term a red line a line in the sand a thin red line a brave and defiant stand against great odds and to redline meaning to go beyond an engine's maximum safe performance level i am sorry to say it but for someone who claims to be a lexicographer and language editor mr zimmer ought to be ashamed