Apodion.net

This Word is most commonly used in speaking of a Number; where I should think Fewer would do better. No Fewer than a Hundred appears to me not only more elegant than No less than a Hundred, but strictly proper.

Baker 1770

How Baker’s opinion came to be an inviolable rule, we do not know. But we do know that many people believe it is such. Simon 1980, for instance, calls the “less than 50,000 words” he found in a book about Joseph Conrad a “whopping” error.

The OED shows that less has been used of countables since the time of King Alfred the Great–he used it that way in one of his own translations from Latin–more than a thousand years ago (in about 888). So essentially less has been used of countables in English for just about as long as there has been a written English language. After about 900 years Robert Baker opined that fewer might be more elegant and proper. Almost every usage writer since Baker has followed Baker’s lead, and generations of English teachers have swelled the chorus. The result seems to be a fairly large number of people who now believe less used of countables to be wrong, though its standardness is easily demonstrated.

Merriam-Webster’s Concise Dictionary of English Usage via, as always, Language Log

I swear to god, people, I could do this all freakin’ day.