You know how alternate-history doofuses are always asking tediously plausible questions like "What if the South had won the Civil War?" instead of cool ones like "What if Eli Whitney had invented Pac-Man instead of the cotton gin?" Of course you do. That's how so many blanded-out retro acts seem to think too: "What if Ian Curtis had lived to front New Order?" If anybody cared, they could probably guess the answers to questions like that. The Scissor Sisters, on the other hand, mangle music history in such an endearing way that you wish their version were true. The oft-campy New York quintet behaves as though "the Seventies" were in fact a single genre--as though Al Stewart and Roger Waters were members of the Bee Gees and recorded their debut, Abandoned Luncheonette, with Phil Ramone and Thomas Dolby. (The Sisters rarely crib from more honorable studio-rock sources, like early Steely Dan--that would be cheating with a capital CH.) If this approach sounds potentially disastrous, well, it is--half the excitement of listening to the band's full-length debut, Scissor Sisters (Universal), comes from constantly anticipating a catastrophic kitsch implosion. Yet the only track that sags beneath the weight of its influences is the lone cover: a discofied "Comfortably Numb," complete with front man Jake Shears squeaking "I-I-I" like a multitracked chipmunk. The originals (bassist and keyboardist Babydaddy does most of the writing) are firmly girded by the band's attention to craft: they truly love the detritus they recycle. Best of all is "Mary," a straightforward piano ballad that Shears sells with such understated sincerity I'm half convinced the Sisters really could cross over to Lite FM. They'd class the joint up considerably. $12. Friday, June 4, 10 PM, Double Door, 1572 N. Milwaukee; 773-489-3160 or 312-559-1212.