What a tragedy that David Gordon Green, who looked like the new Terrence Malick back in the days of George Washington, has devolved into a manifestation of late-career Mel Brooks. Green’s last, Pineapple Express, was clever and liberating — a near-perfect surprise. Your Highness is a low-rent mulching of A Knight’s Tale, The Princess Bride, The Year One and A History of the World, Part 1 by way of 2010 throwaway humor, and smeared with the fart-joke sensibility of the bloated Danny McBride.