Hall was fortunate in having the hardest-working music director on earth and, beyond that, the most collegial. Sir Antonio Pappano set ego aside, deferring often to the Royal Ballet and to the demands of other artists without compromising his authority or integrity. No music director has been better liked. Pappano was supposed to be leaving at the end of the present Britten-Verdi-Wagner season, but he has put himself down for so many productions in years to come that he may never go away. Both companies have installed clearsighted creative directors in Kevin O'Hare and Kasper Holten; the Dane recently rolled out his plans all the way up to the year 2020.

In this rising curve of constant progress, Tony Hall's greatest contribution has been to restore artistic primacy to artists and restrict management to general policy and administration. In doing so, he has redefined the role of opera house chief executive for the 21st century.

In opera, it is the boss's traditional perk (one of them, anyway) to have first and final say on casting and repertoire. Most "intendants" — the title used in Europe  — have early experience as singers or stage directors and consider themselves qualified to make artistic judgments. Even the Met's buttoned-up Peter Gelb is a failed movie director who likes to show artists their best angle. 

Setting aside that directorial prerogative, Tony Hall brought a new sanity to the art of running an opera house. His formula consisted of 24/7 commitment, a dose of common sense, a capacity to delegate and an extensive knowledge of management theory, of which he became a bit of a wonk under John Birt's tutelage. To general acclaim, it worked. There were no major disasters on his watch and the ROH is healthier now in every department than when he arrived.