Peter and Bobby Farrelly bring name recognition to any project that inspires high consumer confidence, guaranteeing die-hard fans a certain level of bathroom humor bravura. But if the brothers are not either writing or directing, watch out. The Farrelly-produced clunker Say It Isn't So is a perfect example of their humor in the wrong hands, those being director J.B. Rogers and writers Gerry Swallow and Peter Gaulke. The Farrelly touches are all there, from cat fellatio to cow groping to sliced earlobes to legless veterans. But these collaborators ape the approach instead of building off its demented logic, making for more groans than laughs, and giving the material the derivative feel of a mangled misquote. Say It Isn't So lacks the breeziness that has distinguished other Farrelly efforts; in a truly dispiriting turn, it hates its characters and relishes their extreme abuse, whereas the underlying sympathy is a lot more evident in a film like There's Something About Mary. Never have the Farrellys written a character so over-the-top unlikable as Sally Field's shrill schemer, nor one quite so grotesque as the surly, robot-voiced stroke victim played by Richard Jenkins. Rogers clearly prefers extremity to subtlety. On the flip side, Chris Klein is way too nice to chart this slapstick territory effectively; his bland charms are far better fitted to the straight-man roles he's played.