Owing to the peculiar fact that thousands of otherwise sensible people maintain a chronic hysteria over second rate ball clubs--football and baseball alike--books about them proliferate. This, the latest, concerns itself with the New York Jets of the American Football League. It concerns itself in such detail that practically every play of the '65 season is described, thus bypassing all but the devout fan. Until last year the Jets were largely muscular mediocrities, but they signed Joe Namath, a cool quarter-back from Alabama, for $400,000 and he may be a super-star of the future. Mr. Curran, who is obviously knowledgeable, has a brisk style and has incorporated a lot of ""color"" about the more diverting AFL players. It is to be hoped that he will be rewarded by a healthy proportion of Jet fans--they turn out 58,000 at a time.