It happened to me in Chichester a long time ago. I was enjoying a peaceful break there, when I suddenly remembered two things. The first was that the school of which I was head was hosting a summer playscheme, and would, at that moment, be filled with happy and boisterous children, supervised largely by young people with more enthusiasm than skill. (“Come on kids! You can yell louder than that!”) The second thing was that there was a cracked plug socket on the skirting board in the main hall, with the innards marginally accessible. I’d spotted it on the last day of term and forgotten to do anything about it. Maybe the caretaker had seen it in the meantime, but I didn’t know enough about his holiday work pattern. I was sure, though, that sooner or later one of the kids was going to poke a steel knitting needle, specially stolen from his gran, into the broken socket, with spectacular results both for him and for my career.

So I found myself in a phone box making the most pathetic call ever made by an experienced head to a local authority. (“It’s just inside the door. No, I’m not actually in the building at the moment. Well, in theory you see... I don’t know... maybe some of that black sticky tape?”) What’s the message here, apart from the fact that it exposes me, yet again, as a triple-distilled dingbat? Mainly, I suppose - and we all know that already - that it isn’t easy to forget school when you’re on holiday.

Perhaps, though, that’s no bad thing.

You’ve heard of Pavlov’s dogs. (Ivan Pavlov, 1849-1936. Feed the dogs and ring a bell, and soon they salivate when you just ring the bell. There’s more to it, but essentially that’s the bit we all know.) Did you know, though, about the time Ivan’s unfortunate dogs were flooded out? They had to swim out of their kennels (Aah!) and so had a break from the experiments. Some of them, apparently, were so affected by the massive interruption in routine that it took them anything up to eight weeks to settle down to routine salivating again.

The message for school leaders is obvious - stay out of the loop for too long and it’s going to be difficult to get back into it. If Pavlov’s pooches are anything to go by, it could take most of the first term before you start drooling with anticipation again.

What you’re trying to regain, against all the odds, given the multiple start-of-term irritations, is what another psychologist, Dr Mihaly (“Mike”) Csikszentmihalyi, formerly professor of psychology at the University of Chicago, calls simply “flow”. According to Dr Mike, flow is a Zen-like sense of being utterly involved in your work - ecstatic, timeless, serene.

When you’re in the flow, says the Professor, “The ego falls away. Time flies. Every action, movement, and thought follows inevitably from the previous one, like playing jazz.”

Many parts of the business community, including Toyota and Microsoft, have flirted with Csikszentmihalyi’s ideas. Leaders at Green Cargo, a Scandinavian transport firm, searched for flow by making managers spend lots more time just talking to their people, one to one in a relaxed way - 90 minutes each, six times a year was the target.

And in school? Well, you may well have been in flow last July - feeling, as you effortlessly suspended three pupils for torching the bike sheds, as if you were adding an inspired trombone riff to a Charlie Parker solo. You lost it over the holiday, though, and now, burned by the sun, hoarse from karaoke, you’re back to the national strategies and the eternal autumn term question of where you’re going for the staff Christmas dinner. It could certainly take eight weeks to get back into the zone. (Yes, it’s sometimes called that, too.) I like the idea of those one-to-one sessions, though. An hour and a half per teacher with a senior colleague every half-term is what it would mean in school. Impossible to find the time? That’s what the Green Cargo managers said, but they did it, and performance improved all round. And thinking about it, if I’d spent more time talking to the caretaker, not only would I have known more about his holiday routine, but he’d have been tuned into my neuroses.

Dr Csikszentmihalyi has written many books. Flow, published as a paperback by Rider, is a good starting point.

Gerald Haigh is a former middle school headteacher