Musicologically, this was the coup of this year's Proms, a piece of history rediscovered. Propheten formed the last part of a Zionist epic put together in the middle 1930s to affirm the cultural values of Judaism at a time when the Jews were under under threat in central Europe. A dramatic oratorio on a vast scale, it was planned initially in Austria, as Der Weg der Verheissung, until - for obvious reasons - the project migrated to New York, where it became The Eternal Road.
As such, it was the occasion for Weill to leave Europe and settle into a new world, a new life, and a new phase of work. And it was pivotal to his development, in that it managed to be both the last of his German scores and practically the very first of his American ones.
But The Eternal Road was never a practical proposition. When it finally reached the stage of the Manhattan Opera House in 1937, it had taken on the dimensions of a monster, with 43 principal roles (including Weill's wife Lotte Lenya as the Witch of Endor) and a running time of seven hours - most of which was promptly cut. The final section had already been discarded. And it stayed so until May this year, when it was premiered in Vienna, free-standing, as Propheten.
Sunday's Prom had huge forces: the BBC Symphony Orchestra and Chorus (plus a children's choir) under Matthias Bamert; 20 soloists; and an attempt at staging, with a token light-show. But it failed. The text - about an archetypal Jewish community, preparing for exile with readings from the Torah - was unengaging; the score was vacuously simplistic, with the mannerisms of Weill's cabaret music, but not its bite; and the performances had nothing to say for themselves either. It only served to reinforce my long-standing belief that Weill is a composer grossly oversold: a minor talent who touched a nerve in Weimar Germany and made good on Broadway, but otherwise peddled very limited wares.
Handel's oratorio Solomon on Tuesday was what you might call a Proms reconstruction - of performances that took place at the Barbican and elsewhere all of seven months ago - and you might well wonder why Nicholas Kenyon wanted to platform the whole thing again so close in time. But that Barbican show was one of the most pleasurably polished things Paul McCreesh and his Gabrieli Ensemble have ever done. And at the Albert Hall, with much the same forces, it was even better: a rare example of period-style baroque working well in such a vast space.
By baroque standards, though, Solomon is a vast piece, scored for double chorus, a string section large enough to divide into 10 parts, and the 18th-century equivalent of big-band brass. Ceremonially conceived, it's short on action but replete with courtly praise for the wisdom, diplomacy and all-round decent- fellow-ness of a king whom nobody in Handel's audience would have failed to recognise as George II.
So the scale was necessarily grand. And at the Albert Hall it registered in all its glory: full and rich, but with razor-sharp articulation, and not a trace of stiffness. Paul McCreesh conducted from the knee (as always), a seductive hula-hooping lilt absorbed into his sense of rhythm. And with a prime cast led by Susan Gritton (Queen of Sheba), Alison Hagley (First Harlot) and the pure, lithe tone of Andreas Scholl, everybody's favourite countertenor, as Solomon (so infinitely preferable to a mezzo), it was a classic Prom: a highlight of the season, and a taste of what we can expect when McCreesh's planned recording - same cast - issues next year.
A few weeks ago, I went to the Holland Park production of Mascagni's Iris, and heard a wretched piece (cute oriental laundress carried off by pimp, to die, for no good reason, on a pile of sewage) wretchedly performed: a show that, like its set, began to fall apart during the opening chorus. This week, I went back for a Lucia di Lammermoor. It was better, but not much: fluently conducted by Tommaso Placidi (a past winner of the Donatella Flick competition), with a capable Edgardo in Jeffrey Stewart, but otherwise undistinguished. Creaky production, risible set. Given that the Royal Borough of Kensington & Chelsea funds Holland Park quite generously, you wonder where the money goes.
Somebody from Kensington & Chelsea should take a look at what I saw last weekend, done far better on the tiniest of budgets at the Iford Festival in Wiltshire. Iford is a Lost Domain-like manor house near Bradford- on-Avon. In its gardens is a small Italian cloister, open to the sky. And in the cloister, with the audience on all four sides around, a company called The Opera Project did a Barber of Seville and a Don Giovanni. Standard rep, and with a cut-down orchestra, and no chorus. But I've rarely felt so physically involved in a performance; and though that was partly because the circumstances were so intimate, I could have reached out and consoled Donna Anna myself, it was also because the presentation was so keenly alive - more than a match for the (often damning) scrutiny of close observation. The promising young Figaro, Grant Doyle, had bags of charm; Guy Harbottle made a dangerously mean Giovanni; and there was a potential star in Benjamin Bland, whose Leporello could have been more varied in its vocal colour, but was otherwise engaging and secure.
The Opera Project is in effect two people: Richard Studer, who directs his own singing translations, and Jonathan Lyness, who conducts his own orchestral reductions. The results speak for themselves, and no doubt will again, when their Barber plays London next Saturday and Sunday at the Chelsea & Westminster Hospital. Entrance is free (don't ask me how, it just is). And you don't have to be ill - though if you were, this sparkling little show would cheer you up.
A final note of apology. An electronic glitch in last week's column metamorphosed Alexander Goehr into Alexander Gopher. No comparison between the Cambridge professor of music and a small burrowing mammal was intended. Honest.
'Barber of Seville': Chelsea & Westminster Hospital, SW10 (0181 846 6821), Sat & Sun 9 Aug.