Santi conducted from memory, and said "I love all of Verdi, but when he composed Rigoletto, Il trovatore and La traviata he was in a profound state of grace.
At the theatre, he also occasionally worked as a prompter, conductor of the chorus, accompanist of singers in concerts, substitute orchestra player and actor on stage.
[2][4] Santi was appointed music director of the Zürich Opera House in 1958, where he had first conducted Verdi's La forza del destino,[5] sung in German.
[2] He remained until 1969, and returned to conduct for decades, including rarities such as Verdi's Ernani, I Lombardi and I due Foscari, Rossini's Semiramide, Bellini's Il pirata and Donizetti's Poliuto.
[5] Santi followed the tradition of Arturo Toscanini, to stay close to the score, accompanying the singers without overpowering them, but restraining "excessive liberties" in embellishments and drawn out notes.