Boilerplate as it can be, David Alvarada's documentary nevertheless offers a rousing assertion that Chicano art is as American as it gets. David Alvarado’s “ American Pachuco: The Legend of Luis Valdez ” offers a crash course through the life of its subject, a pioneer of Chicano theater who helped bring Mexican-American culture into the mainstream with his witty but politically pointed art. Archival footage shows Valdez as an energetic presence in theaters and the frontlines of civil rights