Tangled Tales  Dancers Pull Out All the Stops  The members of
the Alvin Ailey American Dance Theater pounce on choreography
with the zeal of vampires offered a feast of blood, but a lot
more elegantly. Up at City Center, where the company plays
through January 5, they relish everything they do so thoroughly
that I feel almost guilty when I'm less than thrilled by their
material.  Francesca Harper's Apex begins grippingly. Bahiyah
Sayyed-Gaines almost thrashes her super-flexible body out of her
skimpy black bra and trunks. Matthew Rushing crouches, aiming a
spotlight amid smoke. The word fear stretches across the
backdrop; Rolf Ellmer's electronic score menaces the stage.
Clifford Brown ripples and segments his body as if one shoulder
were disintegrating and the vertical human stance were in
question. We hardly need Linda-Denise Fisher-Harrell stalking
watchfully about in stiletto-heeled patent-leather boots to
teach us that this is a corrupt society.  Apex is one of two new
dances (the other is by Lynn Taylor