The very least you can say about Peter Gent's all tough book about pro football is that it's like a cold slow bum and you'll be glad this former Dallas Cowboy has found a longer term career -- he can write. Even if he knocks the teeth out of the illusion that a professional athlete has to be in condition since you'll soon be wondering what kind -- high on grass, amphetamines or just fear -- an intensive, everpresent fear -- even when you're numbed with codeine. Philip J. Elliott, on the receding end of his clays with a Texas team, tells the story which is his as well as that of some of his teammates, particularly Maxwell, a flawless quarterback, probably as good as Joe Namath. And before you're through with the shattering finale, there has been as much assaultive, multiphasic sex as you're likely to read anywhere. A rough book which shafts the whole ugly business -- the equivalent of a strongside blitz, visceral and potent. It is expected to do very well.