Messiness versus cleanliness. Christianity versus heathenism. Free expression versus total repression. There are thousands of ways to raise a family, but only one way to assemble a Wife Swap episode.
Swap's formulaic approach makes it the perfect competitor to Law & Order and CSI: NY, which share its time slot. Amid the glut of reality soaps like Survivor and The Bachelor, ABC has found the ultimate procedural unscripted series: Switch the matriarchs of two families; ask them first to follow and then upend their host family's structure; and end with a 10-minute confrontation between the two clans. Throughout the process, the Margaret Meads teach, learn, cry in minute 33, and return home to ''the best husband in the world.''
Swap's promising pilot in September ended comparisons to Fox's inferior, swap-for-cash Trading Spouses but didn't indicate where the freshman series would go. Halfway through the season, producers have found an upbeat, pat format that, aside from minor flaws heavy-handed voice-overs (less of those, please) and aural cues (gospel music seemed to follow one God-fearing woman wherever she went) has developed into kid-tested, mother-approved (though slightly moralizing) fun.
About that moralizing. Casual viewers won't glean anything from Wife Swap that isn't available from Dr. Spock, but a fairly conservative parenting message emerges upon watching a batch of episodes in a row: ''Dear Mom, Don't work too much outside of the home. Cleanliness is next to godliness (church every Sunday!). Discipline the kids, and if they follow your rules, allow them to use you as a human mannequin, even if you end up looking like a dead ringer for Howard Stern in drag. Love, Wife Swap.''
The Feb. 9 episode busts out a lesbian stepmom (sidebar: ABC pioneered lesbians as a sweeps stunt when Roseanne kissed Mariel Hemingway in 1994) who switches homes with an African-American, religious, B. Smith wannabe. The episode goes through familiar motions straight dad goes to a gay country & western bar, left-behind lesbian cries over yard work but culminates in a jarring coda in which ''B. Smith'' calls the lesbian stepmom's lifestyle ''depraved.'' That moment is the kind of TV that clings to you like a stench, a stench that can't be removed no matter how thorough a Silkwood shower. And although the sentiment is full of hate, it's encouraging to find Swap smelling strongly of something.