Instant nostalgia has become a peculiar byproduct of the new century. VH1 seems to be recycling the decades almost before they're over. Fittingly, lovable comediennes Mo Gaffney and Kathy Najimy have brought back their popular sister act for a reunion tour of sorts after a decade spent pursuing independent careers in TV and movies.

Instant nostalgia has become a peculiar byproduct of the new century. VH1 seems to be recycling the decades almost before they’re over in its proliferating time-capsule series: Don’t look now, but the ’90s are back! Fittingly, lovable comediennes Mo Gaffney and Kathy Najimy have brought back their popular sister act for a reunion tour of sorts after a decade spent pursuing independent careers in TV and movies.

Fans of the duo, who began performing together in the 1980s, greet many of the sweet-tempered characters created by Gaffney and Najimy as they would old friends, chuckling in affectionate recognition of their mild eccentricities. And it’s hard not to warm to these appealingly easygoing performers, Najimy warm and bubbly, Gaffney gruff and wry.

Then again, this “Greatest Hits” collection is a lot like those best-of CDs from once-beloved bands that you buy on impulse while idly browsing at the record store: They turn out to contain quite a few tracks that don’t have the staying power you once thought they would.

This is mildly surprising, since Kathy and Mo never specialized in the kind of radical or insistently provocative comedy that quickly grows stale. They concentrated on bringing out the quirky charm in ordinary folks, mixing poignant observation of universal human truths with gently sculpted caricature.

Much of their material has a lightly feminist bent (Allen Moyer’s set design features a Warhol-style backdrop of female icons ranging from the Mona Lisa to Gloria Steinem to Patsy Cline). In a series of quick takes, they lampoon women’s tongue-tied sensitivity when it comes to discussing menstruation. (Clearly this item dates from the pre-”Vagina Monologues” era.) In the funniest tidbit, they imagine how a pair of football fans would treat the subject if it were a byproduct of the male anatomy. One brags to another: “I use super plus.”

Another sketch finds a pair of ambitious women on the far side of middle age diving head-first into the “women’s studies” experience, confronting the exotica of a vegan restaurant (“These tree trunks must be seats — watch out for slivers in your fanny!”) and the more aggressively avant garde brands of performance art (“Anywho, she has with her a watermelon…” ).

Of course, performance art no longer makes quite the splash it once did as the butt of jokes: The performers’ sendup of a pair of earnest feminist artists declaring fierce pride in their feminine power (“Oh, live in the great uterus of womanhood”) is more quaint than truly funny today.

Other pointedly political items also tend to be date-stamped in neon, as in a monologue for Najimy as a middle-class woman whose amiable chatter gradually turns choked as she speaks of her nephew’s battle with AIDS.

More effective, if also dated, is Gaffney’s portrayal of a Southern conservative manning the barricades at an anti-abortion protest, seasoning casual recollections of her own abortion with brutal shouts of “Baby killer!”

Director Mark Brokaw has assembled the evening with a careful eye for contrast and balance, although the performance would be stronger without an intermission. Many of the skits tend to milk their laughs a little too long, so trimming wouldn’t be a problem. Still, the audience couldn’t get enough of the most touching of the sketches, wisely served up last.

It’s an understated but sharply observed encounter between a fulsomely affectionate old bar fixture, Hank (Najimy), and Karen Sue (Gaffney), a worn-out younger woman marinating her dissatisfactions in wine spritzers. He badgers her with flirtatious offers of marriage until, in a moment of sober misery, she decides to take him seriously. Both performers are at their best here, warmly conveying the bruised humanity in this sweetly pathetic pair while still allowing us to see the humor in their predicament.

Current trends in entertainment seem to favor the malicious exploitation of ordinary folks’ delusions. How refreshing to see them treated once again with a little dignity.

Afterbirth: Kathy and Mo's Greatest Hits

Second Stage; 299 seats; $60

Production

A Second Stage Theater presentation of a comedy revue in two acts written by Mo Gaffney and Kathy Najimy. Directed by Mark Brokaw.

Creative

Set, Allen Moyer; costumes, Linda Ross; lighting, Mary Louise Geiger; sound, Jon Gottlieb; production stage manager, Pam Edington. Opened June 17, 2004. Reviewed June 15. Running time: 2 HOURS, 5 MIN.

Cast

With: Mo Gaffney, Kathy Najimy.
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