Haldeman, one of the more interesting younger science-fiction novelists (The Forever War, All My Sins Remembered) is also a short-story writer of brisk ability. Whether he is dealing with a nuclear blackmail of nuclear powers, an attempt at personality-reconstruction through ""overlay therapy,"" or a computer trying to stymie a gypsy curse, he breezes through the narrative with an effortlessly appropriate pacing which convinces you that you are confronting an idea rather than a gimmick. So what is missing? Only, perhaps, the willingness to take artistic risks, to be outrageous. There is much to admire, nonetheless, in the deftly juggled chills of""Armajas Das"" (the gypsy-curse number), the neat wrinkle on the soldier-as-automaton metaphor in ""The Private War of Private Jacob,"" and the witty account of a hapless ""Balt-Washmond"" citizen drafted into the municipal computer-system as a cyborg component (""Juryrigged""). Fluent craftsmanship, with tantalizing hints of something more.