Inpolitics and business, the French have developed a penchant for cohabitation – even though it invariably ends in tears. François Mitterrand, the late socialist president, found cohabiting with Jacques Chirac, the rightwing prime minister, pretty tiresome. Mr Chirac found the same when he became president and had to work alongside Lionel Jospin, a socialist prime minister,.

In business, various attempts at sharing management power have provoked fierce internal battles with usually only one person coming out on top. This was the case at Peugeot-Citroën back in the 1980s when the Peugeot family brought in Jacques Calvet to flank Jean Paul Parayre, the car group’s chief executive. Mr Parayre lost the battle and Mr Calvet eventually took sole charge.