David Lister: Nice sex, shame about the play

It's certainly one of the more bizarre arts stories of the week, if not the year.

People have been spotted not just texting and talking, but canoodling and even, to judge from reports, "pleasuring" one another in the audience at West End theatres. The relatively new trend of theatres allowing audiences to bring drinks into the auditorium might be a factor in this. But whatever the reason, the actors are becoming restless.

Patrick Stewart and Rosamund Pike were among performers who complained this week about new, low levels of audience behaviour. Theatre, it seems, has its own barmy army.

I have to say, I don't quite get the thrill of sex in the stalls. The seats are pretty uncomfortable at the best of times and very expensive. There must be better places.

The top West End producer Nica Burns is now employing security men to eject rowdy and boisterous audience members. Are they then handed over to the police to be formally charged? "I'm sorry, sir, but you and this young lady are under arrest for indecent behaviour during the second soliloquy in Hamlet. We also have reason to believe that you were indulging in an obscene act in one of the tragicomic debates on the human condition in Waiting for Godot. We have decided to ignore a suspected act of indecency during Tom Stoppard's Arcadia, as the boys down the station agree it does get a bit wordy."

Perhaps the answer is for immoral acts in the theatre to be confined to the upper circle so as not to disturb the actors. Such behaviour is pretty rare, I suspect, and I am more concerned about other forms of disturbance in the stalls. This week I saw Jez Butterworth's fantastic new state-of-the-nation play Jerusalem at the Royal Court, with a mesmerising central performance by Mark Rylance. The play opens with a young girl on stage singing the hymn "Jerusalem". At the performance I attended, a gentleman in the stalls decided to sing along. I don't think he was inebriated. My hunch is that there was an involuntary trigger in his brain which jerked him back to his schooldays and morning assembly. The poor girl on stage looked bemused. Singing along – even at musicals – is an immoral act. At straight plays it must be stamped down on. Offenders should be ejected.

And then there's laughter. That in itself is not a crime. But excessive, and excessively loud and forced laughter can spoil even the smartest comedy. I would particularly like the new security guards to pounce on people who laugh uproariously during Shakespeare's comedies, and to use G20-style force on anyone even giggling during the porter's speech in Macbeth. Such people are not genuinely amused; they are showing off their English degrees.

I also think a strict three coughs and you're out policy should be instituted. Playhouses are not hospitals. Neither are they cinemas. Unwrapping sweets is noisier than a passionate embrace.

There's plenty for the new theatre security guards to get worked up about. But I shouldn't worry too much about sex in the stalls. It's not going to happen often, and if it does, it must be a pretty boring play.

An aphorism a day is the Cohen way

The new memoir of the American showbiz lawyer Steven Machat, which is published next month, has a memorable exchange with Leonard Cohen. The singer tells Machat he is going later that day to the temple. Machat teases him about observing a Jewish festival, saying: "I thought you were supposed to be a Buddhist." Cohen replies: "I want to keep all my options open. Maybe Buddha, maybe God."

Machat then asks him: "What are you doing now?" Cohen responds: "You know how it is, Steven. We humans are always looking for things to do between meals."

Did Cohen, I wonder, always come out with great aphorisms every time he opened his mouth? He seems to eschew small talk for lines that are potential album titles. Or potential titles of an autobiography.

Pity the poor comedy critic at this time of year

The only funny line that I can recall in my years covering the Edinburgh Festival was not actually intended to be funny and was, immodestly, about myself. I wrote a slightly negative piece about women on the stand-up circuit and received a lecture in print from the comedy critic of Time Out magazine, culminating in the angry last line: "David Lister should expose himself to more female comedians."

I'm trying. I'm trying. This year's Edinburgh line-up has a wealth of comedians, female and male, and it could be a vintage year. My heart does go out, though, to comedy critics and also to newspaper readers at this time of year. Every paper is full of comedy reviews from Edinburgh, but how do you actually review comedy? Give away the jokes and you spoil the show for everyone still to see it; don't tell any of the jokes and you are left annoying readers with meaningless descriptions of a "wonderful routine about a bus journey".

It's tricky. No wonder the one thing that comedy critics have in common with comedians is that they never smile.