On Facebook, Peter K. Fallon responded to my guest post on dictionary fundamentalism at Merriam-Webster's A Thing About Words with this comment:
"I'm not a fundamentalist by any stretch of the imagination, and being a teacher I'm more than familiar with the liberties the popular mind takes with language, but I believe there is some fine line (somewhere) where the postmodern conceit that language is unable to faithfully map reality threatens to become true without due respect for standard form."
I am sympathetic. I have respected Bill Walsh's attempts to arrive at a reasonable prescriptivism for sane sticklers, I teach as well, and I feel an obligation to give my students sound advice about the realities of writing and editing beyond the schoolroom rigidities and superstitions they bring with them.
And the fundamental reality is that there is no one correct way to speak or write. My own post-Modernist sense is that there are registers and subjects and occasions and audiences, and a competent speaker or writer must find a balance among them.
Even in the dialect that we call standard written English there are a multitude of registers: academic, technical, journalistic, with variations in convention and formality; and the able writer must calibrate vocabulary, syntax, and tone to match subject, occasion, and audience. It requires judgment, and you do not arrive at judgment by mechanically following a set of simple-minded made-up rules.
If it were easy, it wouldn't have to be taught.