I'd always wondered why the beret worn in France's mountain regiments is much bigger than those worn in other regiments. “That's because it was designed to be stuffed with straw so that you could then put your feet in there and keep them warm,” Delphine laughs. Brought up in Grenoble at the foot of the Alps, Delphine was naturally drawn to a mountain regiment, although it wasn't the one she started out in…