Presumably only someone born in 1971 Ben Zimmer can consider 1975 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 3 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