"In 1992 my co-authors on a book waited until I was away and then secretly replaced every "he" in our text with "he/she," as if I wouldn't notice. Obviously I went ballistic and had them change it back."
It could be worse; the print editor idiot retyping the formulae..
And \epsilon, \varepsilon and \in look so alike.
Like Cassius (or was it Crassus?) it's Greek to them.