Is Plotlessness OK in Mad Men?

Don looking as perplexed as I feel in "Far Away Places."

Since the fifth season of Mad Men premiered a month ago, the "super viewer" blogosphere has sung its praises. Like it did the last four seasons. Just this past week, AVClub wrote, "There are few shows on the air more effective...at portraying how the feeling of everything spinning out of control can seem completely normal in the moment." Slate's TV club gushed, "This was an episode with two marvelous set pieces--Roger's excellent adventure with Jane, and Don's Howard Johnson noir."
I've been watching too, but with less enthusiasm than the typical super viewer. Though I agree that Mad Men gives you great set pieces, are these set pieces enough?

Since Season Five premiered, it has featured episode-long story arcs that beautifully depict how a particular person reacts to a particular set of circumstances. This week, there was the acid-trip that showed Roger's struggle to be hip when his age betrays him. Meanwhile, Don's trip with Megan suggested that he still abides by some classic fifties concept that a husband can control his wife. Last week, the office wet blanket, Pete Campbell, was beautifully pilloried in a series of awkward sexual encounters, culminating in his getting beat upon by Lane Pryce, the company's treasurer. Each of these vignettes highlights some aspect of the characters' personalities. But is this what we really need five seasons in? We already knew that Roger was insecure. We didn't need three episodes this season showing him buy people's loyalties with cash. We also learned that nothing comes easily for Pete the first time he unsuccessfuly flirted with a woman who wasn't his wife in Season One. Five seasons in, the sets are still gorgeous; the costumes are historically accurate, but the plot is starting to stagnate.
Mad Men wasn't always this way. While the show has always been relatively slow paced, there was some mystery and surprise. I was originally hooked by Don's secret in the first two seasons. Would his co-workers and wife find out that he's a Korean War deserter who took on another man's name? How was Peggy going to climb the corporate ladder after bearing Pete's illegitimate child? Now that these story arcs have been resolved, the characters need other challenges that force them to evolve--not just interesting situations that allow them to stay the same.

More and more, Mad Men is starting to resemble the John Cheever short stories that critics have linked it to since inception. Each week features a character in a challenging social situation (the surprise party, the long-absent husband's homecoming, the multi-racial sleepover). How he or she responds (getting embarrassed, kicking the husband out, hesitating before leaving the purse with a black girl) gives us insight into the characters, and his or her environment. In this way, each episode is actually a terrific introduction to the characters for uninitiated viewers. Indeed, last week episode, "Signal 30," even ended with Ken Cosgrove reading out loud from his Cheever-esque short story.

Though I love Cheever, and I love short stories, I'm not sure I want my TV shows to dramatize them. After all, this is a medium that gives writers nine hours over the course of 13 weeks to craft a couple compelling narratives with a beginning, middle, and end. Why waste them telling longtime viewers what they already know when they could be used to create richer challenges for the characters?