> but has the word evolved to mean nine-tenths? I am mindful of the linguistic rule that usage determines propriety, not the other way around.

Howdy, CatMan, or is it Eris? You certainly threw the golden apple in with your first post. As it happens, the OED apparently records the earliest written examples of today's "extended" mening of decimate as occurring in the early 1800s, so there is no member of this board, no matter how advanced in years, whose parents were alive when this particular shift happened. Perhaps in a few years time, when we celebrate the bicentennial of this evolution, the arch-prescriptivists will be ready to concede defeat on this one word. Will that be too soon for your taste, wwh?