The Tour de France often treads an invisible fine line. Most of the time the enormous travelling circus of the world’s biggest annual sporting event has an irrepressible energy and momentum that dwarfs any one person, rider, team or event. At others, something happens to demonstrate just how close this huge freight train of colour, noise and festivity is to coming off the rails.

It has happened before thanks to rider disqualifications in 1904, two World Wars, and the Festina drugs scandal of 1998. In 2016 the Tour sailed perilously close to that line again with almost farcical scenes on Mont Ventoux on Bastille Day, when heaving crowds forced the pre-race cavalcade of motorbikes to a halt and Richie Porte,Bauke Mollema and the yellow jersey Chris Froome piled into the back of it.

In the swirling, caravan-toppling, windy maelstrom on the slopes of Ventoux, with weather so wild that the finish had been moved off the summit to the relative shelter of Chalet Reynard six kilometres down the mountain, the integrity of the Tour looked as precarious as it had ever done.

Debate raged about the jury’s decision to award Froome the same time as Mollema and keep him in the yellow jersey, while turning a blind eye to the jaw-dropping (and technically illegal) scenes of him running up Mont Ventoux in his cleats, and the footage that emerged of his main rival Nairo Quintana holding onto a Mavic neutral service bike for a tow through the crowds.