How many divisions does the pope of Walden Puddle have? Several, political commentators like to say, since when Garry Trudeau draws a line, millions of eyes faithfully follow it to the end, even when the end involves a tour of President Reagan’s brain–though in the case of Reagan’s brain, sundry newspapers dropped an editorial curtain over the offending comic strip, and the millions must have dwindled. Trudeau is a valuable man, in short, and it’s very nice to see him collaborating with Elizabeth Swados on “a partisan revue” at The Village Gate. There are seventeen songs in the revue, each more partisan than the last. “Rap Master Ronnie,” the title song, offers a rap routine intended as a “Reagan Campaign Message to Minority Voters,” in which the President soullessly recites herky-jerky rhymes over funk rhythms, while Secret Service agents breakdance and chant backups. “Say, we want Ron, the cat’s pure sex,/he’s the man who signs your monthly welfare checks.” In “The Class of 1984,” four revolting yuppies croon, “We’re entry-level assholes on the rise” and come out for social