I consider “The Godfather, Part III” the ultimate “what if?” of motion pictures. It's clearly not at the same level as its predecessors, but it could have been a masterpiece if not for a few surmountable glitches. What if a more experienced actress was cast in the pivotal role of Michael Corleone’s daughter? What if Robert Duvall had agreed to reprise his role as Tom Hagen (my favorite character in the series)? What if Francis Ford Coppola had been given more time to develop the project? This third entry of the series still feels like unfinished business after all these years, and Coppola seems to agree. His new edition comes with the title he wanted to give the film all along: “The Godfather Coda: The Death of Michael Corleone.”