At the beginning of the summer John Twelve Hawks’ “The Traveler” seemed an obvious summer smash. The author is anonymous, but it has failed to take off and “the novel’s disappointing start illustrates the risks and advantages of having an unknown author. With luck and the right story, an anonymously written book can seem like a secret everyone is dying to learn, a book that sells itself. Otherwise, the publisher has to depend on the slow, uncertain process of reviews and word of mouth.”