How much do you reckon Jeremy Corbyn weighs? How does he measure up if you compare his looks to Prince William’s? How stylish would you say Andy Burnham is? And, if you had to guess, what kind of product would you say he uses in his hair? The answers to these questions do nothing to help us decide who would make a better leader of the Labour party. But they do influence how voters perceive candidates. The Mail on Sunday’s profile of leadership candidate Liz Kendall describes her as a “slinky brunette” and a “power-dressing Blairite” with a “lithe figure” who “remains Ne