The credits had not finished rolling on Mad Men's series finale, Person-to-Person, before the analysis of the show's final moments began to be dissected. Had Don achieved nirvana in Northern California? What was the meaning of that Coke ad? Were we supposed to assume Don created it or that it was simply a paean to the power of advertising? Was the finale good/bad/ambiguous?
Writing my weekly recap the next morning, I was not entirely sure what to make of things. On the one hand, having Don achieve a zen-like acceptance of himself after jettisoning his entire life, going on a 3,000 mile hobo journey, confessing his sins to one of the few people (if not the only person) in his life whose opinion he valued, and then breaking down in a teary puddle when a stranger named Leonard summarized his entire miserable life in a succinct three minute monologue would have opened a potentially new chapter for Don with an optimistic grace note that was also of a piece with the cultural trends of the early 1970s that were inward (and eastern) looking after the tumult of the 1960s.
On the other hand, if Don's enlightenment was used in service of creating an advertisement that trafficked in that sensibility to sell soda, it would be incredibly cynical and also entirely consistent with a show that started its run with its main character telling a woman he was attempting to seduce that love was manufactured to sell nylons and was never afraid to manipulate his own life story in the service of selling consumer products. 
The ambiguity lingered until Wednesday, when show runner Matthew Weiner was interviewed and essentially confirmed that yes, the bell-ringing-smile-on-Don's-face-Coke-ad connection was intentional. He said, "In the abstract, I did think, why not end this show with the greatest commercial ever made? In terms of what it means to people and everything, I am not ambiguity for ambiguity's sake. But it was nice to have your cake and eat it too, in terms of what is advertising, who is Don and what is that thing?"
Weiner went on to lament people who viewed the ending with a jaundiced eye, saying "I did hear rumblings of people talking about the ad being corny. It's a little bit disturbing to me, that cynicism. I'm not saying advertising's not corny, but I'm saying that the people who find that ad corny, they're probably experiencing a lot of life that way, and they're missing out on something. Five years before that, black people and white people couldn't even be in an ad together! And the idea that someone in an enlightened state might have created something that's very pure — yeah, there's soda in there with a good feeling, but that ad to me is the best ad ever made, and it comes from a very good place ... That ad in particular is so much of its time, so beautiful and, I don't think, as — I don't know what the word is — villainous as the snark of today."
After reading Weiner's comments, my initial reaction was, "Did he watch his own show?" Seriously. What was the point of curling Don in the fetal position after Peggy called him a monster, or shedding tears in California while telling Anna he had "ruined" his family, or Sally walking in on him in flagrante delicto with the neighbor lady, or his secretary hurling an object at him after they slept together and he blew her off, or being minimized as a "man, in a room, with a checkbook" when he offered to help Anna, or Betty telling him she preferred their children live with her brother than him because he was such a bad father,  or any of the myriad other awful instances of Don's bad behavior and the aforementioned hobo jag if all that did was lead him to a place where he could imbibe the cultural zeitgeist and turn it into an ad for soda? I could not think of a more cynical way to end the show than to essentially turn it into a Rust Cohle-ian proof of concept that "time is a flat circle." 
And don't get me wrong, I like the cynical solution because advertising is cynical and the show was cynical - people were consistently horrible to each other, they lied, cheated, and stole, so why are we asked, after 92 episodes, to suddenly put on the rose colored glasses? As Don reminded us over and over again, advertising is premised on selling happiness, of letting people know that things are ok even if the world is going to shit. Whether it is Burger Chef drowning out the noise of Vietnam or Dow Chemical selling Joe Willie Namath as American as apple pie while the Notre Dame fight song plays, it seems impossible to put a smiley face on the idea that that the key takeaway from Don nuking his whole life and landing in a Northern California commune was how to build a better TV ad.
If all of that wandering just put Don right back where he started, what was the point of having him shed his entire existence - his job, his apartment, and one million of his hard earned dollars - not to mention the soul baring he did to Peggy or the bonding he did with Leonard, if all that bought him was the ability to distill his ability to make his wants our wants in the form of an ad that manipulated the universal desire for peace on earth in service of selling sugar water?
At the same time, it was totally consistent with who Don is as a person. As the critic Heather Havrilesky long ago observed, if you scratch an inch below Don's surface, all you get is more surface. Redemptive Don was someone we knew well - be it telling Birdie he hadn't been "respectful" towards her (the delicate way of saying he'd dipped his quill in many New York City ink wells), coming out of Anna's death with a new attitude on life, being a (mostly) good husband during the honeymoon period with Megan, or clawing his way back into SC&P after his Hershey meltdown,  Don was rarely as convincing as when he had bounced back from yet another rock bottom, but those attempts at turning a new leaf were never availing, so why wouldn't we, as viewers, be skeptical about the idea that this time would be different?
Jon Hamm offered his own take, observing that "When we find Don in that place, and this stranger relates this story of not being heard or seen or understood or appreciated, the resonance for Don was total in that moment. There was a void staring at him. We see him in an incredibly vulnerable place, surrounded by strangers, and he reaches out to the only person he can at that moment, and it’s this stranger. My take is that, the next day, he wakes up in this beautiful place, and has this serene moment of understanding, and realizes who he is. And who he is, is an advertising man. And so, this thing comes to him. There’s a way to see it in a completely cynical way, and say, “Wow, that’s awful.” But I think that for Don, it represents some kind of understanding and comfort in this incredibly unquiet, uncomfortable life that he has led."
This is as reasonable an explanation as any other, except for the history of the entire series and Don's total and unremitting belief that people don't change  and nothing from slugging a tee totaling bible thumper to admitting his own lies and deceits to Dr. Faye Miller, Peggy, Megan, or the guys at the VFW had ever changed that.  Indeed, the entire end of the series was about Don giving up his life and all its trappings, but if Matt Weiner and Jon Hamm want us to believe Don is/was redeemed and that led to nothing more than the creation of an iconic commercial and not, say, becoming a better person, that strikes me as totally cynical.
1. Smoke Gets In Your Eyes, Season 1, Episode 1. The two most obvious examples of Don manufacturing a fictional version of his actual life are the Kodak "Carousel" pitch, where he used slides of him with his wife and children to tell a story of nostalgic longing and love even as he was a philandering husband and largely absentee parent, and the Hershey pitch, which started off as a totally fake story of Don being allowed to pick out a candy of his choice at the corner store by his old man after mowing the lawn but collapsed into a searing admission of his true association with the candy bar - as a treat for picking the pockets of the johns on the whorehouse where he was raised. The Wheel, Season 1, Episode 13, In Care Of, Season 6, Episode 13.
2. The Quality of Mercy, Season 6, Episode 12, The Mountain King, Season 2, Episode 12, Favors, Season 6, Episode 11, The Rejected, Season 4, Episode 4, The Good News, Season 4, Episode 3, Person-to-Person, Season 7, Episode 14.
3. True Detective, The Secret Fate of All Life, Season 1, Episode 5.
4. Meditations in an Emergency, Season 2, Episode 13, The Summer Man, Season 4, Episode 8, see e.g., A Little Kiss Parts I & II, Season 5, Episodes 1 and 2, see, e.g., The Strategy, Season 7, Episode 6, Waterloo, Season 7, Episode 7.
5. The Mountain King, supra.
6. In Care Of, supra, Hands and Knees, Season 4, Episode 10, Person-To-Person, Season 7, Episode 14, A Little Kiss, supra, The Milk and Honey Route, Season 7, Episode 13.