Argument for serial comma (actual story description): Merle Haggard: The documentary was filmed over three years. Among those interviewed were his two ex-wives, Kris Kristofferson and Robert Duvall. [link]
Jo Walton offers her take on this:
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Some people may say we've seen it all before, but I thought Merle Haggard was a truly classic cowboy film.
Here we have two men riding into a small town, two very different men who have nothing in common except that each of them bears the scars of having spent a decade being married to Merle. We can see the way Merle (and Merle's aftermath) has shaped both of their lives -- and Merle, although dead before it begins, shapes the film the same way.
Duvall is a cowboy, taciturn, reclusive, and you can still see how very gorgeous he must have been when he was young. Kristofferson is a singer who won Merle away from Duvall with a song. (The chords of the song haunt the movie, but we do not hear the words until the end.) They were once rivals for Merle's love, but now that Merle has been murdered they have to work together. They come to what's first a grudging respect for each other and later an actual friendship with just a hint of romance. The final shootout is beyond tense, and the last moments brought tears to my eyes.
People will compare this with the old chestnut Brokeback Mountain, but the difference goes far deeper than just shepherds vs cowboys. Brokeback Mountain focused on the angst of being gay and a shepherd. Merle Haggard leaves the angst out -- these men are rough Westerners who just happen to love other men. And lets face it, the position of women in the Old West has always been ambiguous. The lives and loves of cowboys have always been each other -- Merle Haggard just makes explicit what so many other films from Butch Cassidy and the Sundance Kid on have left implicit. What women we do see are well done -- Kristofferson's sister-manager, Duvall's niece, and Sue, the saloon-keeper who knows everybody's secrets. The film is stronger in that nobody questions the direction of anybody's sexuality, it turns instead on who they love and how long love lasts. All right, the real Old West wasn't like that, but it wasn't like Shane either, and people always make films for a modern sensibility.
It's nonsense to call Merle Haggard a documentary, however. This is a western pure and simple. I'm glad I saw it, and I shall be buying the DVD as soon as it's available.