The Sundance Film Festival was famously conceived to showcase independent film, and encourage aspiring young directors. But it’s been so successful that it’s now difficult to separate the world of the indies from mainstream Hollywood. A new book drives home that point by looking at the history of the festival, as well as at supposedly “independent” studio Miramax, which was actually sold to Disney more than a decade ago. Of course, “Sundance wouldn’t be Sundance without people grousing about celebrities, all while running from movies to parties featuring those same celebrities,” so it’s possible that the whole debate is missing the point.