I am not, perhaps, Vogue’s target audience (too many adverts for clothes, not enough cricket and offal) but I gave a loud gasp when Grant, the diary hobbit, staggered in with gossip about its next cover stars. Admittedly this was because Grant had stepped on my foot but I may as well pass the news on. It will, he squealed, be none other than Princess Beatrice and Princess Eugenie. I confess that I shrugged but Grant says this is a proper scoop. After all, the PM reads Vogue. The royal appendages, his source told him, were photographed at the Royal Lodge in Windsor, with their mother desperate to slip into shot. The Duke of York walked in and saw his daughters with all their…