One of the contemporary production books for Don Carlos thus austerely sums up the Philippe–Posa duet in Act II (of the five-act version); its none-too-subtle indication of grand themes handled seriously is one that has consistently driven the piece's reception. As so often, Verdi himself encouraged the trend – most significantly by treating the duet to more substantial revision than any other major piece in his entire output. Some drastic cutting occurred even during rehearsals, so that the supposed Urfassung predates the first performance. What is commonly referred to as the ‘original’ version corresponds, then, to the music performed at the 1867 Paris première. This was substantially refashioned for Naples in 1872 (with Italian text only), and given an even more thorough overhaul in 1884. The four versions have been much discussed: indeed, revisions such as these were one of the proving grounds on which Verdi (and thus his admirers) became musicologically respectable. Where would we stand today without those four versions and their many Verdian copains? Possibly on some other, less comfortable podium.