There’s a grail, but it doesn't glow in a mundane if perverted Christian ritual. Three of the main characters have young and old actor versions and the “wonder-working spear” is a knife in a Cain and Abel story superimposed on Wagner’s myth (as if that wasn’t complicated enough). Kundry, whom the composer defines as literally flying between “good” and “bad” worlds, enters primly in the first two acts bearing a tea-tray.

The score is effective, and rewarding to perform, but derivative. The libretto uses every cliché, or truism, about save-the-planet youth activism in the book; it’s didactic, not dramatic. Direction, design and lighting sometimes feel unfinished. Yet as a youth/community opera, Glyndebourne’s latest educational project hits the mark; the commitment of singers and players young and old, professional and amateur, makes the ends justify the means.

Richard Strauss described conducting Wagner’s Tristan und Isolde for the first time as "the most wonderful day of my life". It’s understandable that Glyndebourne’s music director Robin Ticciati should wish to improve upon “wonderful” in conducting a concert staging in 2021 with "miraculous" in charge of the full Nikolaus Lehnhoff production. I challenge anyone to cite another Tristan more alert to every possibility – the electrifying, the ferocious, the transcendental.

How much better can a classic get? Sebastian Scotney more or less asked the same question on theartsdesk the last time Giulio Cesare returned in triumph to Glyndebourne. I never saw David McVicar’s justly famous production of what has to be Handel’s most consistently inspired opera live before, but I wonder if every single number can ever have been applauded, as it was last night.

Why would anyone want to stage a work like The Merry Widow in this day and age? Silly question. It’s the music, stupid. Of course, it’s an entertaining story and there are some good jokes. But I'd bet that if Heuberger had composed the music to this libretto, as he started doing, instead of Franz Lehár, who took it on afterwards, I wouldn't now be writing about Cal McCrystal’s new Glyndebourne production, or anyone else’s for that matter.

Five years after it first clattered onto the Glyndebourne stage, André Barbe and Renaud Doucet’s visually exuberant Die Zauberflöte – featuring everything from dancing carcasses to a monster made out of blue-and-white crockery – continues to dazzle as much as it entertains.

It’s what you dream of in opera but don’t often get: singers feeling free and liberated to give their best after weeks of preparation with a master conductor. Glyndebourne Music Director Robin Ticciati leads the way with a peerless London Philharmonic Orchestra in Bizet’s absolute masterpiece, and Tunisian-Canadian mezzo Rihab Chaieb’s Carmen stuns in a vocally magnificent cast.

As a human being of immense warmth, humour and erudition, Andrew Davis made it all too easy to forget what towering, incandescent performances he inspired. Now is a good time to recall those properly to mind, to listen to his huge discography, and to assess his proper place among the top conductors – again, as one of such versatility and range that, to adapt what Danny Meyer writes below, he might have been labelled a jack of all trades when he was a master of all.

Choosing a limited best seems almost meaningless when even simply the seven operatic experiences I've relished in the run-up to Christmas (nothing seasonal) deserve a place in the sun. But in a year which has seen Arts Council devastation versus brilliant business as usual where possible, English National Opera – faced with “Manchester or die” – needs the first shout-out for doing everything the moneygivers want it to.

It never rains but it pours – and hails, snows or, above all, thunders. The presiding tone of Semele, in Adele Thomas’s new production for Glyndebourne, matches the current English summer with its grey skies, glowering clouds and stormy outbursts. Jove’s evidently in a rage, despite his rejuvenating lust for the Theban king’s daughter, Semele. He’s not the only one: the first of many lightning-bolts – designed by Peter Mumford with Rick Fisher – that flash around Annemarie Woods’s crepusular set illuminate lonely Juno, spurned and seething spouse of the heavenly overlord.