I doubt there is a teacher in the land who can't, off the top of his or her head, think of one set of parents at least who will have their finger permanently cocked on that trigger. Well might you groan: Mrs Highflyer wants an investigation into why little Julia only got A-minus in her Mandarin mock GCSE, whereas the O'Hippies say that it is evil to give homework to a 12-year-old in Glastonbury week, so chill, man. Mr and Mrs Hypersex consider that the PE teacher was "inappropriate" when she told their busty 12-year-old to wear proper pants under her tiny tennis skirt ("Why was she looking? Is she a lesbian?"), and the McComma family are appalled at the Year 8 history teacher's misuse of the apostrophe. Meanwhile, Khafiya's mum says it's blatant discrimination leaving her child out of the netball team just because she wears a full niqab at all times, and Charleen's dad says that his little princess had her human rights breached when she was asked to empty her pockets on the school trip to Dieppe. Even though this did result in the discovery of three shoplifted thongs and a bent spliff. And now they're all on the phone to Ofsted.
Groan, drop head in hands. Conversely, you might cheer for Chief Inspector Christine Gilbert and pour scorn on Christine Blower of the NUT and others who wring their hands over the suggestion. Who, after all, is the customer here? And what is it they say about customers? There were short periods during my own school-parenthood when it would have been handy to have the school managers know I could feed them to the wolves if they didn't sharpen up their pastoral or academic act. But these periods were short and they were always resolved either by calm diplomatic discussion or (on one occasion) by removing the child, with an oath. And two of the four schools were private and already vulnerable (the ATL conference heard recently that members are dismayed by the ultrasensitivity of independents' heads to complaints about teachers. They tend to sack them fast, it seems). But anyway, looking back, most of my complaints were curricular rather than school-based. They were about things such as infuriating Baker-days, the moronic food-tech syllabus, wally AS levels, ghastly set books, abominable exam timetables and all that. So we were all on the same side, which was cosy.
"Parent power", of course, has moved on - you can crunch league tables, raise money to start a Trust school, and when you grumble to the local authority, since last year they have had a "legal duty to respond formally", which makes one wonder what they did before (two fingers?). There are to be open competitions before a new primary school opens, and so forth.
Unfortunately, the power that parents want most - to choose their favourite school, get a place and sit back with a sigh of relief - is the one they don't have. Probably never will. Government is now so resigned to the existence of a good few horrible schools that it has resorted to admissions lotteries: without noticing that the one thing lotteries are famous for is producing disaffected losers.
But the thing about "parent power" that always unnerved me, even in my PTA heyday is, frankly, the other parents. It is one thing to give them the power to blow the whistle on a seriously chaotic school, and quite another to declare open season on academic matters and encourage every neurotic headcase to fret that a perfectly good school is - horrible word - "coasting", and that the main symptom of its lack of "excellence" is that their child isn't yet a Nobel prizewinner.
Parents are seen by government as important "drivers" of standards, but face it: we are unreliable, unpredictable engines at best. We are partial: we want only the kind of teaching that best suits our own child, and don't care a rap for the others (I'd have been perfectly happy with a school with no ball games, which my children disliked; others would happily do without drama or music as long as the school teams won cups). Moreover, we are naturally short-termist. We want the school to be terrific for the few years that our child is there. After that, it can coast downhill as fast as it likes. Unedifying, but true.
Another problem is that we have highly fragmented views about ethos: some parents want Singaporean-style zero tolerance of fights, fags and fumbling. Others want a "supportive" approach to troublemakers and a benign blind eye turned to their tricky progeny. Some want boys to be boys; others want them to be quiet. Some want Assembly with "To be a Pilgrim"; others want hip stuff about Diwali and the environment; others want breakfast to be served instead. All of us are confused by memories of our own schooldays, good and bad; and most of us have day jobs that have nothing to do with education.
We are really not best qualified to interfere with the minutiae of school life. Sad for us, but there it is. We have to trust you. Until the awful day when it proves impossible not to.
Libby Purves, Author and presenter of 'The Learning Curve' on BBC Radio 4.