The Dance Theatre of Harlem's third and final program, which will now alternate with the first two for the rest of the week-long Kennedy Center engagement, has the look of an assortment put together to woo the unconverted, using the most superficial of means. One supposes that the thought behind it was that those who might not take easily to the formal intricacies and expressive subtleties of classically oriented ballet might yet be swayed by the body beautiful, as exhibited in high-voltage displays of energy, flash and color.

The evening certainly had its rewards along these lines, and there may well be audiences that will succumb more readily to such blandishments. But you only get out what you put in. What such programs ultimately prove is that ballets whoe only merit lies in a show of physical charm and dexterity cannot transcend their exploitative basis, and that the lasting appeal of dance depends on thoughtful and artistically uncompromising choreography.

The hardest to take of the program's four items was the "artiest" one, Glen Tetley's insufferably long "Greening," to an outer-spacey score by Arne Nordheim. Like so many other Tetley ballets, it gives you the feeling of watching a box of eels -- it's nothing but incessant wriggling, stretching, curling, twisting and flipping, without discernible pattern, rhythm or meaning. Even the lovely Virginia Johnson, with her impeccably beautiful line, couldn't add much savor to it.

The "Corsaire" pas de deux might have provided some kitschy fun, but Elena Carter and Eddie Shellman appeared surprisingly unequal to its virtuoso requirements last night. Geoffrey Holder's pulsating Afro-Hindu fashion show, "Dougla," at least has some show-biz glamor and rhythmic exhilaration about it, and Robert North's "Troy Game" leavens its trite sport-dance parallels and macho stereotypes with genuine humor. In these two pieces the showing-off didn't pretend to be anything else, and the DTH made the most of it.