It was the lesson of the UK general election and it's the big 'takeaway' from Cannes too: prediction is a mug's game. All week the chatter was that Todd Haynes' lesbian love story Carol was set to collect the Palme d'Or – or that Holocaust drama Son of Saul from first-time director László Nemes would triumph. In the last few days a consensus began to form around The Assassin from Taiwanese director Hou Hsiao-Hsien; according to British bookmakers, The Lobster was the one to beat. But when Jacques Audiard's Dheepan was announced as the winner, the response was a collective “really?” For all the pundits, critics' panels, insider gossip, statistics and God knows what else, few had picked it. Oh well: c'est la vie.