It’s a bit Prada, a bit Gaultier and contains traces of the famous phys ed scene in Clueless. Wearing a black bustier over a white shirt has transformed from micro to massive in the trend stakes this season, with everyone from Olivia Palermo to Tash Sefton sampling the look. Why? Well, the combo provides the warmth of winter layers without the usual clumsiness associated. Plus, it’s an easy, palatable way to get the old bustier out in the cooler months. You can keep those clavicles covered… for now.