Can English ever be correct now?

In the ongoing debate between language prescriptionists and descriptionists, I generally sit somewhere in the middle (but a little to the side of the people who believe there is a right and a wrong way to say something). With English as fluid as it is, there’s no real point in telling people that they’re doing something wrong, and besides, the fact that the language grows and changes so fast is one of the best things about it.

However, I recently read a blog post on Wordnik that made me stop and think. In updates of dictionaries, definitions of words are sometimes edited for length, modified, or added to (reflecting the changing use of language, of course). However, what happens when an integral part of the definition is removed altogether?

In the latest update of the OED, the definition for orthoepy was changed slightly, from “correct, accepted, or customary pronunciation” to “accepted or customary pronunciation” (draft edition September 2010). It may not seem a big change, but I feel that the missing word ‘correct’ is crucial. How are we supposed to have a standard if we only know what is commonly used? I know that in many cases the popularly-believed concept becomes somewhat acceptable, but where do we draw the line? How will I prove I’m right when I’m having an argument with someone who pronounces ‘pronunciation’ ‘pronounciation’?