“Critics didn’t have much use for the re vival of David Mamet’s “American Buffalo,” which closed Nov. 23 after just a week of performances. But they weren’t alone in their indiffer ence. To hear backstage sources tell it, Mamet himself could barely be bothered with the play, which is generally considered one of his best. He never attended a rehearsal, didn’t see a performance and refused to do any press for it.”