628-page books, even when they're first novels, aren't supposed to be promising; they're supposed to deliver. But for all its aura of mastery and intimations of grand design, Tauber's ""epic"" of the late Sixties supplies bulldozer evidence of talent instead of anything approaching an engulfing read. Surely he is to be commended for resisting the obvious tugs towards a campus setting; hero Tyler Bowen is distinctly postgraduate, a gifted biologist assigned--on a milicratic whim worthy of Waugh--to serve as pussyfooting, cover-upping Public Information officer at an Arizona government lab hiding the ""World's Biggest Secret,"" the latest in unspeakable germ weaponry. While drop-out brother Willie (""The Kid"") Bowen turns up MIA and later an unintentional hero in a Vietnam of idiotic orders and insolent troops, Tyler (""Babe"") wriggles under authority's dumb thumb, trades smart-asseries with any and all, and--from ""a democracy of tissues embracing his slim monarchy"" (that's sex, folks) to McCarthy/Kennedy primary campaigns--messes with unhappily married Tucson reporter Johanna, whose eyes are ""the exact blue-green color of a xenon oxide laser beam."" Tauber can write simple and tight--Johanna's rape at knifepoint by a desert hitchhiker, Willie's escape from a VC ambush. And he can unroll ironies and similes with enviable, if overkilling, funds of comic energy and allusion. But competing styles bring tedium and turn-offs: Times-Op-Ed-pompous for commentaries on Life; pop-journalistic for reprises of Main Events (Sirhan Sirhan, Kent State); just-folks mixed with socio-scientific jargon--""linear"" and such--for chat among the thinktankers; and deep purple for love, sex, and honor. Without a focusing voice, the Sixties slide down to the inevitable despair and disillusion, but the echoes and seminars along the way--baseball, feminism, ecology, technocracy, ""Lyndon's bladder scar""--can be expected to grab those-who-were-there if they're ripe for a tenth reunion.