Apropos the past Sunday: Against a few decent dads in opera — Peter of Hansel und Gretel, William Tell, Gianni Schicchi — the genre is teeming with bad ones, such as Giorgio Germont in La traviata, Alberich in Wagner's The Ring of the Nibelung (Wotan at least has some feelings for his dozens of offsprings), King Philip II in Verdi's Don Carlo, Cenerentola's f