Prom 71: Trifonov, Staatskapelle Dresden, Thielemann

Soft power in the shape of cultural ambassadors can go a long way. With a little help from its big guns in banking and industry, Germany has given this year's Proms no less than four of its major orchestras – from Leipzig, two from Berlin, and now from Dresden: all the more reason to wave those EU flags on a typically international Last Night in three days' time.

There's even been co-ordination this week in the shape of Mozart piano concertos and Bruckner symphonies three nights running, first from Barenboim and now from Christian Thielemann. A failsafe interpreter of the Austro-German repertoire, you'd have thought. But that was to reckon without the Mozart of Daniil Trifonov (pictured below taking a bow) and even Thielemann's own occasional shortcomings in wit and humanity.

In Mozart's Piano Concerto No. 21, the adulated "Triff" – labelled "The Greatest", but actually only one of many outstanding Russian pianists performing today – turned triffid. Such cultured tone from the Dresdeners in the opening bars; would the pianist match up? He stole in almost imperceptibly; his subtlety in solo and handsomeness in ensemble promised much. But the nuances verged on the etiolated, and then he went off the rails just before the first-movement cadenza.

Which turned out to be his own, an odd combination of the artistic, counterpointing themes in a way that Mozart would surely have applauded, and the grotesque. The corresponding cadenza in the third movement was much worse; injecting a note of pain into a blithe vivace is one thing, but steering it towards the 20th century Russian piano repertoire? I'm no purist about cadenzas – last season Elisabeth Leonskaja made an effervesecent case for Britten's in Mozart – but this last one made me laugh for all the wrong reasons. Which the finale as a whole didn't, but should have. Thielemann, not noted for his sense of humour, sped it along with articulate playing from the Staatskapelle, but not a hint of wit.

The slow movement – yes,  the one starting with the Elvira Madigan theme – tested the Barenboim principle of drawing an Albert Hall audience in rather than reaching out, with spectral, floating violins, but further ghostliness from the pianist sucked all human life out of it. Even Trifonov's encore, Prokofiev's transcription of the Gavotte from his Cinderella ballet, lacked spike. Hunching over the piano rather than sitting upright with weight from the shoulders is never going to get the right fullness of tone.

Surely Thielemann's Bruckner would be peerless? Well, the cultured Dresden sound, so beautifully blended, so perfectly middle European, certainly was. In the performing version of 1876-7, shorn of the Wagner quotations which make the original such unwieldy fun, the calms either side of the first movement's central turbulence, the first with atmospheric horn solo to match the flute and its quirky chromatic questioning (player uncredited in the programme), were vintage Bruckner.

Less impressively handled were the two appearances of the "song group", one of the composer's most inspired, but so loosely conducted that strings felt out of synch the first time, and were decidedly at loggerheads in the recap. The same threatened to happen with the sublime viola tune at the heart of the solemn slow movement, though its religious cadences linking with Mozart were beautifully done.

Thielemann's unqualified successes were the Scherzo and the tricky finale. His elastic style is perfect in Austrian dance music, and if I take away one miracle in the mind from the Prom, it would have to be that tripping polka with trombones beneath perfectly intoning a calm chorale. Until Bruckner's clumsy and unfathomable injection of a reminiscence from earlier in the symphony when we should have reached the close, the volatilty held everything together. Let's hope Thielemann finds his more consistent form in Beethoven, Reger and Strauss tonight.

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