Rolando Villazón at 40 is back on reasonably stylish form, as far as the voice will allow him to go – which is not always up and volume-wise only just as far as the Covent Garden Balcony. John Copley’s Royal Opera Bohème is two years younger than the Mexican tenor. It burns less warmly than the faltering stove in the first act, casts a pall over collective attempts to reanimate the naturalism which is all there in Puccini’s perfect score, and needs a second interval to drag its weary bones back up the stairs to the students’ attic in Act Four.

Much more regularly than the seven years it takes the Flying Dutchman's demon ship to reach dry land, the Zurich Opera steamer moors at the Southbank Centre. None of its more recent concert performances up to now has branded itself on the memory as much as its 2003 visit, when chorus and soloists stunned in Wagner's Tannhäuser.

My phone's predictive text posed an interesting question. Robert le Doable it insisted on calling last night's opera. And it's often been asked of this and other grands opéras. Are they doable? Such was the munificence of the times in which they thrived, and such has been the collapse in their popularity, are grands opéras worthy of resurrection? And do we have the resources and good will to do justice to their singular vision? If any opera company could meet the all-singing, all-dancing demands, it is the Royal Opera House.

Lehár’s Merry Widow has been been spreading enchantment across the globe for well over a century. She’s the vintage champagne of operettas, and the prospect of John Wilson popping her cork was more than a little enticing. Wilson, one feels, instinctively knows how this music goes and indeed did so before even the composer put the notes on the page. He was surely born into the wrong century. So why do I feel a "but" coming on? Why did this particular magnum of bubbly not go to my head?

We had already been reassured in interviews that Calixto Bieito’s production of Carmen would not be shocking, although perhaps this was more a warning to those of us hoping that it might be. Bieito’s radical reputation is well earned, although approaching 50 he is by no means an enfant and clearly not so terrible anymore either.

You can tell a lot about a performance of L’elisir d’amore from the two pizzicato string chords that so neatly take the sheen off the military pomp of the opening phrase. Played well, these subversive little asides can throb with all the wit and cheeky self-mockery that elevates this opera above the hundreds of Donizetti also-rans. Played earnestly, as they were last night however, they heralded a rather limp performance – laboriously correct without ever finding (let alone seizing) that anarchic glee that riots through the score.

Clearly rents in 2010 were substantially cheaper than I remember because somehow Rodolfo and Marcello have managed to find a garret in Soho of all places. And it would be easy to continue my review in this vein, poking the odd hole in OperaUpClose’s updating of La Bohème, including mentioning my temptation to shout out, “Pawn your laptop for some Covonia, mate, your girlfriend’s got a right cough on her!” But none of those quibbles were really the point of this production.

John Bunyan’s Christian, hero of The Pilgrim’s Progress, may have been putting his feet up in the Celestial City for the better part of 350 years, but for Ralph Vaughan Williams’s Pilgrim it has been a rather different story. Languishing in the Slough of Despond after an unsuccessful first run at the Royal Opera in the 1950s, the composer’s lavish “Morality” The Pilgrim’s Progress, with its patchwork biblical libretto, vast forces and uniquely blended combination of opera and oratorio, has never since established a secure place in the repertoire.

At the heart of Julian Philips’ chamber opera The Yellow Sofa stands, perhaps unsurprisingly, a beautiful antique yellow chaise longue that bears witness to all the adultery, money grabbing and revenge that a 1880s Lisbon household has to offer; but Philips’ sofa is far from mute, she is portrayed here by the exceptional Lauren Easton who sings an extraordinary mix of opera and fado as she narrates, in a sultry yet haughty fashion, all the steamy goings on.

“Last night’s tenor was superb, wasn’t he? Such Italianate passion at the top of his range…” In the pub, the streets and – in this case – over the cereal and croissants of a hotel breakfast, there’s only one topic of conversation in Wexford for 10 days every autumn: opera. During festival time this tiny Irish town on the river Slaney undergoes something of a sea-change. Doctors, plumbers and shop-assistants all transform themselves into the festival staff, ushering audiences, erecting staging and assisting artists.