As I remember, they had also localised symbolic "constants" so a format spec fed to (some date function) was 'dd/mm/yyyy' for english locale, but 'gg/mm/aaaa' for the italian one . God help you if you had (I did) some combination of - say - English Excel and italian OS (as I remember you got english function names but italian 'constants' as in DATEFORMAT('gg/mm/aaaa'...) with nonsens errors if you used 'dd/mm/yyyy').

An asinine idea indeed.