With Tropic Thunder —the product of Ben Stiller's harrowing journey into the heart of retarded darkness— storming multiplexes today, the film's stars are going into promotional hyperdrive. And nothing sells your movie more than some old-fashioned controversy—particularly one in which you're accused of being insensitive to the disabled. (Semitic advocacy groups, meanwhile, surprised everyone by seeing nothing objectionable in Tom Cruise's minstrelsy, Jewface performance.) On the GMA hotseat today was Stiller and co-star Jack Black, both of whom calmly explained that in matters of insensitivity and bodily function, context is everything; framed by the movie's central comedic conceit of actorly self-indulgence, then, not a single dropped R-bomb or ass-bomb should be considered anything other than purely satirical.