FOR an unprecedented fourth week running, Ed Balls managed to keep his hands to himself at Prime Minister's Questions on January 29th. There was hardly any of the violent finger-stabbing the shadow chancellor of the exchequer, seated two sword-lengths from his Conservative opponents, loves to indulge in - and no airing of his favourite taunt, a fluttering hand movement that Mr Balls uses to signify Britain's flatlining economy. Good Keynesian that he is, the shadow chancellor has noticed that the facts have changed: according to figures out this week, Britain's economy is growing at its fastest rate since 2007. His latest gesture, hands clenched tightly around his inner thigh, face meanwhile tense and puce, suggests some discomfort with that. Yet the taming of the Labour bruiser, Westminster's most boisterous, obstreperous and, according to the Tory prime minister David Cameron, annoying man, is part of a wider campaign. Labour's leader, Ed Miliband, wants to raise the tone of PMQs, the shop-window of Britain's raucous parliamentary democracy. This is noble. As Britain's principal state theatre, an exercise in setting the agenda for public debate and testing the mettle of the prime minister, PMQs has a long and glorious history. Yet in its present form, a 30-minute weekly debate held every Wednesday at noon, it has become a farce. As the prime minister rises, to answer the first of a dozen questions, he is greeted by a sonic wall of jeering and invective. Flashman! Labour backbenchers scream at Mr Cameron - almost no matter what he is saying - in reference to his supposed alter ego, the public-school bully from "Tom Brown's School Days." "Apologise!" the Tories holler at Mr Balls, referring to his lack of contrition over past Labour spending. "Back-stabber!" they sneer at Mr Miliband, who won the Labour leadership against his brother David. It is great sport - which is why a million people watch PMQs on television in Britain and elsewhere. In America and Japan it is cult viewing. Tony Blair, still bruised from his latest encounter with William Hague, a brilliant Tory debater, was often dismayed to hear his performance at the dispatch box critically appraised by Bill Clinton and George W. Bush. Both presidents were avid fans of PMQs on C-SPAN. Yet the "giant joust," as Mr Blair called it, has long since failed to shape public debate - which is why Mr Hague won no votes for his hits. This is partly for the same reason that Mr Miliband is trying to raise the tone of it. Many voters find the sight of their elected representatives behaving like drunken hooligans off-putting. "My constituents are mesmerised by PMQs but hate us for it," says a Tory backbencher. It is perhaps no coincidence that none of the three most popular politicians in Britain, Boris Johnson, Alex Salmond and Nigel Farage, is an MP. At a time of historic disaffection with mainstream politics, as suggested by collapsing support for both Labour and the Tories, this is a big concern. And Mr Miliband is not alone in it: when Mr Cameron became Tory leader in 2005 he also swore to end "Punch and Judy politics." Yet the magnitude of his failure is astonishing - Mr Cameron is an exemplary dispatch-box brawler - and for Mr Miliband instructive. The hyper-adversarial culture of Westminster is fundamental to PMQs and, it may well prove, impossible to rein in. It reflects the House of Commons" layout - it is unusual in having government and opposition benches in opposing lines. It is fuelled by the party system, in which the virility of the leader - including, thanks to a change wrought by Margaret Thatcher, his ability to speak for any of his ministers - stands for the tribe. On the Labour backbenches, Mr Miliband's more sotto voce recent performances have caused dismay. It is also impossible, in the white heat of parliamentary debate, to distinguish between strategic and tactical objectives: many Tories view Mr Miliband's civilising gambit as a sign of weakness, Labour having recently been hammered on the economy. And if they will not play ball with the Labour leader, what then? PMQs this week offered clues to that. Against the Tory din, Mr Miliband maintained the interrogative tone of a firm, rather exasperated, schoolteacher. It was a show of steel, not weakness. But the biggest cheers from his backbenchers came when Mr Cameron briefly mislaid a note, when one of their own shrieked "Hear! Hear!" a little too loudly, and when a Tory MP, Penny Mordaunt, who recently learned to dive for a reality TV show, stood up to speak. "Splash!" the house roared. This is not a culture Mr Miliband can change by fiat or even by his own example. That's the way to do it Yet that is not all bad. PMQs fulfils its other mandate, testing the prime minister, amply. All holders of the office hate it. Harold Macmillan regularly threw up beforehand; Mr Blair called PMQs "the most nerve-racking, discombobulating, nail-biting, bowel-moving, terror-inspiring, courage-draining experience in my prime ministerial life, without question." Given the difficulties of holding government to account, this is not to be sniffed at - as Thatcher acknowledged: "No head of government anywhere in the world has to face this sort of regular pressure and many go to great lengths to avoid it." There are ancillary benefits, too. Terror of being exposed at PMQs ensures prime ministers are well briefed on the performance of their ministers. Forcing party bosses to turn up for the joust also provides backbenchers with an important opportunity to buttonhole them. If Mr Miliband fails in his endeavour - as probably every MP bar one expects - this should console him. Perhaps that chastening experience might even persuade him to temper some of his other grand schemes to change Britain's political and economic systems, according to the social-democratic model he favours. That would have another ancillary benefit: an end to Mr Balls's dejected thigh-clenching. The shadow chancellor, a more pragmatic Labour politician, would rather stand up and jeer.