Isabel Gotzkowskys retrospectiveincluding the new th(RE)a(D), where shes connected to Jon Zimmerman by a yard of cloth the color of bloodstainsdemonstrated her virtues as performer and dancemaker: physical and emotional pliancy, strength that engenders tenderness. Her costumers have a good eye for fabric and color. But Last night I had a dream, danced with Zimmerman, points up a persistent weakness. Slave to the rhythm, Gotzkowsky accelerates moves when the music heats up, and the duet looks hectic. Movements in pieces like Fly . . . but don't often tell us little that is new as they proceed but merely fill the time Gotzkowskys occasionally irritating music choice demands. You want to hand her an old 45something under four minutesand say, Put down the Arvo Pärt, use this, and show me what ya got! And the Jewelry Rule should apply to any retrospective: Take one piece off and leave it home.