Failure haunts Giles Coren. Ten years ago, he published a work of literary fiction, “Winkler,” about an angry and rude young man at odds with the world. “Winkler” was panned by the critics, didn’t sell many copies and was largely ignored. Giles revisits the process of writing and publishing his only novel, all in an attempt to discover if it really was as bad as they say it was.