Two Christmas comedies are currently striving to bring holiday cheer to Bay area audiences, but neither, I'm sorry to say, will slip the most savory sugarplums into your hungry psyche. Still, Sister's Christmas Catechism is harmless and well-meaning, while The Santaland Diaries is worth a smile (and a welcome back to one of our best actors). If moderation is your thing — moderate amusement, moderate stimulation — you still might want to catch these decidedly mild entertainments. But if it's bellylaughs you crave, well, you're barking up the wrong evergreen. If the Grinch purloined these two shows, I doubt anyone would notice.

Let's play dress-up. Several years ago I saw Late Nite Catechism at the Jaeb Theatre of the Tampa Bay Performing Arts Center, and I was delighted with "Sister" (Mary Zentmyer), the dour, opinionated nun who was scandalized by the latest changes in Catholic doctrine, and who treated all of us in the audience like naughty, crude third-graders.

Well, success breeds sequels, but not all sequels can be successes. Sister's Christmas Catechism features a much less terrifying Sister (Kathleen Stefano) who's more concerned with staging a tepidly silly Nativity scene than with rapping our sinful knuckles and collecting money for the "pagan baby fund." The current Sister — at the Jaeb again — is still likely to impound the audience's chewing gum and confiscate a noisy cellphone, but beyond that the similarity ends. This friendlier (and less funny) nun wants to share: She wants to hear our stories about Christmas calamities, she wants to reward us for knowing the historical identity of Santa Claus, she even wants to reminisce about appearances of the Virgin Mary in Clearwater and on a fabled grilled cheese sandwich.

As every Freudian knows, humor exists where we're most nervous, where we try to repress thoughts, but this Sister is too amicable to reach into our guilty depths. Instead, she wants to please us: to tell us a bland joke about Pope John-Paul II when he got to heaven, to warn us against buying Obsession perfume for a holy sister. Perhaps the limpest gambit of the whole evening is her promise to unravel the mystery of the Magi's gold: Was it stolen, and if so, by whom? The question is of no importance, the method she insists upon is of no interest (who had the motive, opportunity and proximity?), and the solution is entirely insignificant.

Similarly, the whole of Act 2 — the choosing of audience members to play parts in a Nativity scene and then the dressing of those spectators in one silly costume after the next — might entertain a roomful of children, but is sadly lacking in adult content. Late Nite Catechism worked so well because it treated adult spectators like those children Auden wrote about "who have never been happy or good." But the sequel seems only fit for kids — and well-behaved ones at that. Nothing edgy is ventured, and nothing satisfying is gained.

Of elves and men. Brian Shea is one of the very best actors in the Tampa Bay area, a performer with more keys on his piano, arrows in his quiver and tricks up his sleeve than 10 other thespians put together. So if he can't make David Sedaris' The Santaland Diaries a riveting success, probably nobody can. And he can't.

But it's not his fault. The fact is that Sedaris' memoir about a Christmas season during which he played an elf at Macy's Santaland just isn't all that surprising. It's full of predictable figures: the obnoxious adults, the clueless children, the ungenerous Santas and the baffled, innocent Sedaris trying to make peace with it all. Shea does everything to make the tale funny: He puts on distinctive voices for the different characters, parades around in yellow pants and silly green slippers, even tries to sing like Billie Holiday (his only failing: I've heard Sedaris do a far better job on NPR). Kudos to American Stage After Hours and director Drew DeCaro for putting Shea back in the public eye after too long a layoff. But he deserves better than The Santaland Diaries. Did someone say Shakespeare?