With "Inside Llewyn Davis,"John Goodman delivers another of the short but forceful performances that have become his specialty. The film, which opens nationally Friday, follows a disenchanted Greenwich Village folk singer in 1960-61. Mr. Goodman isn't the title character. He plays a gasbag old jazzman and drug addict named Roland Turner who spends almost all his time harassing the singer. Wearing a purple jacket, a Caesar haircut, and a bushy gray goatee, Turner coughs awake in the back seat of a car headed toward a possible gig, sees Llewyn with a guitar, and growls: "What are you, a flamenco dancer?"...