Joaquin Phoenix took his Andy Kaufmanesque “acting and grooming bore me” character to Letterman last night, and poor Dave had to deal with terse, one-word answers and general dickishness throughout the painfully awkward interview. For the sake of clarity, let’s all just go ahead and stop saying that Joaquin is “acting erratically.” He’s acting, yes. Acting like an asshole. For a documentary. A documentary about him being an asshole.