John McIntyre notes on his blog You Don't Say that a man named Rod Gelatt, a retired professor of journalism who taught at the Missouri School of Journalism, writes in a letter to the Columbia Missourian newspaper (responding to an article calling for more attention to correcting grammar errors in online content):
in the announcement of the invitation for us to become grammar police, I found two errors: "….who wants to generously point out…" (splitting an infinitive) and "Spell check won't help you when you have the wrong word to start with" (ending sentence with preposition).
I ignore the first point (split infinitives have always been grammatically correct in English; see for example this page). And as for the second, stranded prepositions have also always been grammatical in general, of course; but with respect to Mr Gelatt's example, I wonder what he thought the "correction" would be? The common phrases to start with and to begin with are among the (numerous) cases where stranding the preposition at the end of the phrase is not just permitted in Standard English, it's obligatory.
That is, You can wipe that smile off your face to start with is grammatical in Standard English, but *You can wipe that smile off your face with which to start is not. So Mr Gelatt has it ass-backward: not keeping the preposition at the end here would be the grammatical error.
I agree with John McIntyre that it is a bit scary to think that this man spent a career "standing before the impressionable young" and packing their heads with arrant nonsense that editors like John ultimately have to try and rectify by returning the victims to a state in which they can write their own native language sensibly.
It's another illustration of why I am worried that prescriptivism harms the economy: think of the senselessly wasted thousands of hours each year as dim-witted journalism professors with old-fashioned ideas teach falsehoods about English out of hundred-year-old books of toxic waste (you know which sort of book I mean) so that editorial staff members of newspapers can later spend their expensive time struggling to shake the poor graduates out of their didactogenic misconceptions and get their writing back into a state where it's fit to publish.
Addendum: A particularly dumb comment that originally appeared below said this:
IMHO, the words classified as "prepositions" are, in fact, prepositions ONLY when they are in the "pre-"position in prepositional phrases. Otherwise, they are simply one-word adverbs of location or direction. In verbal forms such as "to start with", the "with" is a meaning-mandated adverb which may occur in any normal adverbial position. If you take this view, the whole question of "stranded prepositions" simply goes away.
I couldn't bear to let such painfully misinformed pomposity ("I[n] M[y] H[umble] O[pinion]", indeed!) remain on the Language Log site; yet it seemed churlish to attack one of our guests. So I deleted the comment, and present its contents anonymized here for correction. It certainly is painfully misinformed, and I need to explain why.
Calling every preposition an "adverb" if it doesn't have an NP complement is the ancient tradition of stupid Latinophilia (notice the assumption that if they are called prepositions they have to be pre-positioned, in accord with the Latin etymology). Sensible grammarians have been trying to do away with it for two hundred years. Jespersen's The Philosophy of Grammar argued for the sensible view, but others preceded him, back to the middle 18th century.
And the idea that "the whole question of 'stranded prepositions' simply goes away" under the ancient stupid view is just a mind-bogglingly awful mistake. Even the proponents of the ancient stupid view agreed that in What can we cut it with? we have a preposition, not an adverb; so stranding remains. The question is whether you are going to deprecate it, and follow the long tradition established by John Dryden, or get in line with all the serious grammatical descriptions of the language, one hundred percent of which agree that stranding is fully grammatical—and much more normal than the rather pompous preposition fronting of With what can we cut it?.
It is clear that this commenter had not been reading Language Log for very long. One place to start reading about the history would be "Hot Dryden-on-Jonson action" by Mark Liberman. But a search on preposition stranding "Langage Log" would bring up a lot more.