There are many examples of Desgrange's self-belief but few as entertaining as the way he fell out with a provincial bike-maker called Mercier. André Leducq, one of France's top riders, had left the Alcyon team to join Émile Mercier. Edmond Gentil, the head of Alcyon, asked Desgrange to leave Leducq out of the French team for the Tour de France, a team which as organiser Desgrange chose personally. That was Gentil's revenge and Mercier was annoyed. Desgrange, though, had taken a decision that, like all Desgrange's decisions, was correct, final and indisputable.

Mercier wrote complaint after complaint, then engaged lawyers. Desgrange ordered his staff never to mention Mercier's name again. Mercier, though, was a sponsor and bike-maker and sometimes had to have his complaints published. So L'Auto compromised by never spelling his name correctly. That drove Mercier into a deeper fury and more lawyers were engaged. L'Auto would again print corrections, only to get the name wrong once more. "Monsieur Gercier has let us known that his name is Monsieur Mervier", and then, "Monsieur Mervier asks us to say that, in reality, he is called Monsieur Cermier". When Mercier wrote once more, L'Auto printed: "Monsieur Cermier insists that in fact he is known as Monsieur Merdier" (Merde is French for "excrement")