Sir Rudolf really has nothing of substance to add to his 5000 Nights at the Opera memoir--so this slight volume is a sad, patchy grab-bag of opinions and anecdotes, along with reprinted memos and letters from Sir R.'s file at the Metropolitan Opera. There are flat one-sentence descriptions of dozens of singers, many of them mere testimonials: Leontyne Price (""a superb singer. . . I am proud to call her a friend""); Leonie Ryasanek (""a superb artist. . . a friend whom I treasure""). There are digs at: music critics (""It is hardly a profession a young man would choose unless there was some negative reason in the background""); the acting ability of singers; Schuyler Chapin (he ""had no idea how to manage an opera company""); Mayor Koch (""I disapprove of the Mayor of New York City wearing short sleeves in public""). There are brief comments on favorite operas, un-favorite operas, Met triumphs and flops, and his managerial style (""The vicious stories that this was an unhappy House were simply true""). And the longest section is devoted to the Bing/Callas correspondence regarding a possible late-1960s Met comeback. None of this, unfortunately, is either fresh or illuminating. Nor do the appendices that fill out the book--lists of every artist employed at the Met under Bing's reign, etc.--add anything. Only, in fact, one section goes beyond sketchy, shallow cut-and-pasting: a short, painful statement on what Sir R.'s life is like today (""I am desperately lonely""), with details on his wife's paralyzing illness. Even for dedicated opera buffs, then--an addendum of only marginal interest.