This is a bit embarrassing. I am always aware, when sprawling around in this space, that I am not a teacher. Quite wanted to be, eyed up a couple of postgraduate certificate in education courses - but bottled out. So I exist here only as parent, journalist, school governor, intrusive novelist and general hanger-on to the coat-tails of education.
If you mighty teachers are rugby legend Jonah Lomu, hammering up and down the pedagogical field against all odds, I am the spotty fan with a rattle in the back row of the stands. It is not my place to tell you what to think.
But someone must be frank. You must control yourselves, you really must.
When you feel that hand itching for the mouse, when the shimmering screen lures you and the warm, welcoming arms of the TES website enfold you at the end of a bruising day, you mustn't give in. You are still on display.
This cyber staffroom has got a large picture window, and all the rest of us - parents, governors, journalists - are out there pressing our greasy noses to that window and gasping. You are shocking us. We get upset easily.
It began a few months ago when the savvy education correspondent of the Telegraph, John Clare, was answering a question about sarky teachers and quoted some of the put-downs suggested by contributors to the TES online forum.
They were breathtakingly nasty: "I bet your village is missing its idiot" and "I hope you look forward to life on the dole" were among the pleasanter ones; others were targeted mercilessly at the insecurities and unhappinesses of adolescence. These were mean bastards, and proud of it. We gulped, and hoped that they were a minority.
From then on I got interested in the forum, and have to say that by and large it reflects well on the profession and its attitudes, with most of the jokes well within the bounds of acceptability. As one said, think of it as Primal Scream therapy. I liked the dilemma of the teacher facing parents' evening and wondering whether "to give it to 'em both barrels about what arseholes their kids really are. Should I?"
One could sympathise. I also liked the sociological observations about whether you can tell how tough a class will be by the names in the register: Liam and Kyle are trouble, but interestingly so is Jessica (though Sophie is a goody-goody, obviously). The cowboy names, says one sage, are always the ones to watch: Dwayne, Wayne, Ryan, Lee. Girls beginning with "Ch" are dodgy, especially Chantelle.
Well, fine. It's interesting. It's shop-talk. It's fun to press your nose to the staffroom window, and make a mental note that your little Dwayne and Charmaine may be up against prejudice when they hit Reception.
But then suddenly a harmless observation by David Waugh on the boredom of exam invigilation loosed another flood of evil teachers onto the website, and the watchful journalists spotted it again and revealed you in all your splendid nastiness. Playing "chicken" with the other invigilator is fine, and we can put up with squeaky-shoe concerts, but do we anxious parents, with chicks going through public exams, really want to know that some of you are playing "Ugly", by trying to stare out the ugliest kid in the room? Or competing as to who can hand out most unwanted fresh paper to bewildered brats who didn't want it? Or playing "Good kid, bad kid" quizzes with the other teacher?
Look, as I said, this is embarrassing. We should know really that you're only human, and need to blow off steam. We shouldn't be surprised if you express the odd cynical view, find some children nicer to look at than others, or yawn at the tedium of watching young minds grappling with the most important hours of their fledgling careers. But we really don't want to know, really, OK?
We want to imagine that each of you is Mr Chips, and that as you stride the aisles of the exam hall you are looking down benevolently on the efforts of anxious youth, wishing them well, exuding affectionate hope for their futures.
It would be nice if a few of you were praying; nuns at my school used to invigilate while saying their Rosary. A lot of you, no doubt, are indeed doing something along those lines, either sacred or secular.
But it would be a real favour to us outsiders if the rest of you - Mr Nasty, Miss Cynical, Dr Pissedoff - would just keep off the public websites and confine your primal screaming to the saloon bar of the Pedagogue's Arms after hours. We're easily shocked. We need to believe that you're better than us: more patient, more dedicated, cleverer.
I'm off for the smelling-salts now, and an hour in a darkened room.
Continue the debate at www.tes.co.ukstaffroom