Contemporary artists come no more flamboyant than Matthew Barney. He’s a kind of all-American superhero garbed in international gallery chic, one whose chosen media include: petroleum jelly that simulates whale blubber; his five stream-of-consciousness “Cremaster” films, full-tilt fantasias that conjure, among so much else, such oddities as Norman Mailer and Busby Berkeley-esque lines of choreographed cowboys; and his own body, which he might transform into a prancing satyr, for instance, or submit to physical restraints during extended exercises, public performances that test his stamina and agility as he tries to create drawings while, say, racing up the side of a wall.