“Sylvia,” the story of a husband, his wife, and the poodle that comes between them, is arguably the most-produced play in the canon of A.R. Gurney, a playwright known for his absurdist, inventive, playfully self-reflexive works. It may also be one of his laziest and weakest, a half-baked domestic psychocomedy predicated on the skin-deep observation that humans anthropomorphize their dogs. Frustratingly simplistic in its point of view and sociologically shallow in its implications, “Sylvia” is not only superficial but artificial, with a denouement hampered by cognitive dissonance.

What “Sylvia” does have going for it, in well-mounted productions, is the experience of watching a human portray the titular dog, a role that has gone to Sarah Jessica Parker and Rachel Dratch in major productions in the past. Watching a grown woman completely succumb to the slobbering, clingy, excitable and sullen actions and demeanors of a canine can create an infectious sense of manic slapstick.

The Boca Raton Theatre Guild, whose production of “Sylvia” runs through Sunday at the Willow Theatre at Sugar Sand Park, rarely hits these comic highs, performed by a ensemble that feels like a blighted chemistry experiment. Jacqueline Laggy plays the talking pooch, discovered in a park by a Keith Garsson’s Greg, a frustrated husband with troubles at his Wall Street workplace and an empty nest at home. He brings the dog back to his wife Kate, played by Patti Gardner in a skillful if humorless performance. Kate wants the dog out as soon as possible, but Greg bonds with Sylvia, creating an interspecies conflict: a woman and dog ­– but the way it plays in front of us, two women — sparring for the love and affection of a man.

There’s nothing wrong with Garsson’s performance; it’s neither exceptional nor problematic, and he seems to enjoy himself onstage. I got another impression from Laggy, who doesn’t commit fully to the canine role. Compared with previous incarnations of “Sylvia,” her hairstyle, demeanor and increasingly shapely costumes are those of a woman, not a shaggy dog, and she walks on two feet, doesn’t give her owner any affectionate licks, and carries objects in her hands, not her mouth. The pup mannerisms are a chore – they don’t come as natural extensions of her character.

This is a fault of direction as much as performance: By downplaying Laggy’s dogginess, eroticizing her in sexy attire, and up-playing her cognizance of the world around her, director Genie Croft has greatly reduced the play’s comic potential and makes the love triangle less funny-absurdist and more creepy-bestial. This decision unnecessarily bolds, underlines, and highlights the comic sexual tension between Greg and Sylvia, which any playgoer should already infer.

As for Mario Betto, who plays three characters – a male dog owner, a society matron and an androgynous couples therapist – the performance is stiff and stilted, not up to par with the professional theater status to which the Boca Raton Theatre Guild has recently been elevated. Gardner’s Kate is easily the star performance here, creating an affecting sense of dramatic depth that might even be absent in Gurney’s original conception of the play. But when this is the best complement I can give a play that is foremost a comedy, there’s something wrong with the picture.

“Sylvia” is at the Willow Theatre at Sugar Sand Park, 300 S. Military Trail, Boca Raton, through Sunday. Tickets are $25. Call 561/347-3948 or visit brtg.org.