Luckily, too, this production cut Idomeneo's final, bind-the-wounds aria, ''Torne la pace.'' Mr. Fortunately, in the following act he revived and finished strongly. Fortunately, this production allows Idomeneo to take the briefer, simpler option of ''Fuor del mar.'' At one point, during a trio at the end of Act II, the tenor suffered a vocal crisis and almost resorted to falsetto. Though noble in bearing and intelligent in handling the all-important recitative, he made heavy work of Mozart's more florid passages.
Jerusalem, known best as a Wagnerian (his Loge currently has no peer), was not in supple voice. The most problematical piece of casting was Siegfried Jerusalem in the title role. Though Miss Vaness rarely emits a caressing tone, she delivered a soaring, house-penetrating sound and found in the role a piquant mixture of high-flown tragedy and wild-eyed, tongue-in-cheek wit. It apparently is still unthinkable to omit Elettra's mad scene (''D'Oreste, d'Aiace'') in favor of her original crazed recitative (''Ah, smania! oh, furie!''), especially when a dramatic soprano like Carol Vaness is available. The final ballet and other divertissements that figured in the original 1781 Munich production - on which the Met bases its version - are missing. The Metropolitan does not adhere to that style slavishly. The production reminds us that Mozart did not closely follow Italian opera-seria tradition in ''Idomeneo'': under terms of his commission he took as his model an ''Idomenee'' by Danchet and Campra in the French Baroque's tragedie lyrique style. Here, the ruined antique columns and changing sepia scrims, suggesting Piranesi engravings of Classical decay, somehow work harmoniously as backdrops to a mixture of Grecian and 18th-century French costumes. In fact, monumentality of design serves ''Idomeneo'' far more truly than it does most other works staged by Mr. Ponnelle's memory, is an appropriate monument to his peculiar genius for magnification. When his production returned to the repertory on Monday evening for the first time in three years, it reinforced one's opinion that this ''Idomeneo'' is the most significant contribution left the Metropolitan by the late director. In 1982, Jean-Pierre Ponnelle mounted an ''Idomeneo'' for the Metropolitan Opera that almost made up for past sins of omission.
Until the New York City Opera made a brave stab at Mozart's ''Idomeneo'' in 1975, neither of the city's major companies had ever produced the work, an oversight difficult to understand.