Katherine (Kate Eastwood Norris) confronts Petruchio (Cody Nickell) in Aaron Posner’s Wild West-style production of “Shrew.” (Carol Pratt)

Presumption of funniness is not exactly a capital offense. But it’s a performer’s crime nevertheless, a rookie sort of miscue that helps to sink Folger Theatre’s ill-conceived spaghetti-western version of “The Taming of the Shrew.”

No one could possibly be more impressed with the antics of director Aaron Posner’s yuk-yuk production than several of the actors themselves. I stopped counting the times they shot the audience winking looks, as if to say, “Wasn’t that a good one?” or “Darned if I get the point of that line!”

Sometimes — and especially in sub-par Shakespeare — an idea takes hold in the rehearsal room that every character, no matter how tangential, is a riot. You can see this error put to practice in Posner’s OK Corral-inspired production, as various actors struggle, to lethally hammy effect, to turn inconsequential ripostes into upstaging bits of extraneous business.

No one is guiltier of attitudinal excess than Danny Scheie, in the heretofore secondary role of Grumio, servant to Petruchio, the brutal wooer of hellcat Katherine. Although the list of characters in the original text lumps Grumio with seven others as Petruchio’s manservants, Folger embellishes the description, identifying him as Petruchio’s “trusty, flamboyant servant.” Thanks — we wouldn’t have known. Employing a voice like the eardrum-splitting wheeze of a strangled cat, and a sibilant “s” that puts you in mind of Carmen Ghia in “The Producers,” Scheie has decided, with Posner’s blessing, that the real shrew is Grumio.

The result of this and other distortions is to throw cold water on the comedy’s main event, the rollicking union-by-fire of Cody Nickell’s Petruchio and Kate Eastwood Norris’s Katherine. It makes little sense, for instance, to turn the father of Katherine and Bianca into their mother — even though Sarah Marshall, as Baptista, gives the evening’s most resonant performance. Would a mother of the Wild West (or wherever the heck Padua and Mantua and Pisa are now located) ransom a daughter as callously as Baptista does? The talents of the amazing Holly Twyford, too, are squandered in the misguided gambit of turning Tranio, servant to Bianca’s suitor, Lucentio (Thomas Keegan), into a woman — and then adding an “As You Like It” twist by having her disguise herself as a man. It’s a joke that goes absolutely nowhere.

Posner has proved himself to be an agile Shakespeare interpreter, as he demonstrated with his revelatory “Measure for Measure” and his thrilling, illusion-packed “Macbeth,” devised in collaboration with magician Teller. One can only assume that in the controversial “Shrew’s” thicket of misogyny and spousal abuse, he encountered subjects he wasn’t comfortable tackling head-on, because this “Shrew’’ is a hodgepodge of concept-laden dodges and sloppy asides.

Set designer Tony Cisek turns the Folger stage into a saloon, in which a character wholly out of Posner’s imagination, the Blind Balladeer (Cliff Eberhardt), strums a guitar and croons twangy tunes of his own composition that comment on the plot. “Life is sad / Life is funny / But when you break it all down / It’s about the money,” he sings, referring to the dowries Baptista dangles in front of the suitors for the comelier younger daughter, Sarah Mollo-Christensen’s far too timid Bianca, and for Katherine. The singer does more to make sense of the plot than do the actors.

When first we meet Norris’s cowpoke Katherine, she gives the impression of being Annie Oakley’s manic-depressive cousin. Dressed in designer Helen Q. Huang’s becoming “Bonanza”- style outfits, Norris enters with a gun strapped to her waist: How a character of her legendarily hair-trigger temper has avoided plugging half the men of Padua is its own mystery. She plops herself down with a bottle of hooch, tears streaming down her face.

Norris, an actress of refinement who can project steely charm, doesn’t seem particularly in her element as a cantankerous tomboy, and, in fact, looks pretty unhappy throughout the evening. An audience has to feel some measure of relish in Katherine’s wrath, as she tries in violent spurts to purge her demons; even the famous scene in which she maliciously binds Bianca is halfhearted. Only in a few pointed moments does a sense of character, and the real possibilities of this “Shrew,” emerge. One of these occurs in Petruchio’s lair, after he’s humiliated his bride through starvation and confounds her expectations by revealing that his roughness is merely a ruse. The look of hopeful relief that crosses Norris’s face feels real.

As Katherine’s sparring partner, Nickell mixes manly authority with an enlightening air of self-deprecation. This is a Petruchio who’s flying a bit blind, who can’t quite believe what he’s pulling off. The look of wonderment that crosses his face as Katherine recites her final, inflammatory speech of wifely obedience — “I am ashamed that women are so simple / To offer war where they should kneel for peace” — suggests a far more sophisticated evening than the one that unfolds on Capitol Hill.

The notion of Petruchio as not quite the sly puppet master he pretends to be would be a promising starting point for a “Shrew” yet to find its way to Folger’s stage. Little of such subtlety finds a hearing in Posner’s unruly schoolroom, where, destructively, nearly everyone seems to think of himself as the class clown.

The Taming of the Shrew

by William Shakespeare. Directed by Aaron Posner. Set, Tony Cisek; costumes, Helen Q. Huang; lighting, Jennifer Schriever; original music, Cliff Eberhardt; sound, Christopher Baine; dramaturg, Michele Osherow. With Marcus Kyd, Craig Wallace, James Gardiner, Dave Gamble, Katy Carkuff, Edward Christian, Rex Daugherty. About 2 hours 40 minutes. Through June 10 at Folger Theatre, 201 E. Capitol St. SE. Visit www.folger.edu/theatre or call 202-544-7077.