A legendary septuagenarian wind player from Switzerland returns to the repertoire with which he made his name 50 years ago, and there's an exciting live reading of a gloomy fin-de-siècle symphony conducted by a contemporary French giant. The same conductor also treats us to a sparkling Stravinsky rarity, and a youthful duo lighten the mood with some Russian fireworks on Merseyside.

Having been away in remote mountain places, I hadn't heard that the BBCSO's chief conductor Jiří Bělohlávek was taking a month off to recover from a virus. So it was a bracing last-minute shock to find the man stepping up to the podium to conduct Wagner's Meistersinger Prelude not the orchestra's wise Hans Sachs but a Walther von Stolzing in conducting terms, tipped unexpectedly by one source outside the BBC as Bělohlávek's successor. Lean and hungry Dane Thomas Dausgaard masterminded the most brilliantly co-ordinated Prom I heard last year, and he excelled again last night. As the programme's central cabinet of curiosities did not.

"O, reason not the need!” cries Shakespeare’s King Lear, insisting on certain unquestioned rights. The phrase came to me listening to Bernard Haitink conducting Brahms’s Second Piano Concerto and Fourth Symphony last night. The 82-year-old Haitink does not question the need for this music - and I’m not sure that’s entirely right. I want the imperative there, I want to feel the urge to be born in those musical paragraphs that Brahms wrote with such generous largesse. To reason the need gives the music its birth again.

Some things just don’t seem to belong in a pairing. The flute and the French horn both have their distinct sonic personality. It wouldn’t be going out on a limb to suggest that the average listener tends to lean towards one or the other. Even Mozart wrote for the horn out of love but trotted out his flute compositions for money. But opposites can and do attract and so it once more proves in a new recording featuring the horn and the flute and, discreetly chaperoning the pair of them, the piano.

Several Prommers fainted, possibly out of boredom, in a longer than ever first movement of the Brahms Violin Concerto. The boredom, palpable around me, came not from pianist Dejan Lazić transcribing the fiddle part for his own pleasure - a communicative musician might have made us forget the original - but from the failure of Brahms's song to soar. Dyspeptic by half-time, I found everything awry: several obscure concert overtures would have worked better than Frank Bridge's Rebus, I'd have preferred many short cello-and-orchestra pieces to Holst's Invocation and thought any conductor might suit Elgar's Enigma Variations better than Vassily Sinaisky. Wrong, fortunately, on the last two counts.

Older pianomanes may lament the passing of the great Russian schooling that gave us the likes of Sofronitsky, Yudina and Richter. I'm not so sure. The younger generations may have dropped the mystic torch, but their more even-tempered approach can beguile. Yevgeny Sudbin forms the current holy trinity with Boris Berezovsky and Nikolai Lugansky. His latest Wigmore recital was revelatory, not always in a good way; that broad beam needn't have swept every corner of the broad Russian church he so singularly constructed in the programme's second half. But anyone who can make Liszt sound as lucid as Haydn is unique.

I’m standing with my feet on peaks and my head in clouds, looking down steep Alps at the tiny chocolate-brown chalets of little Verbier way below on the green slopes. It’s ravishing up here on the top of Fontanet, and I tarry, gloating over the botanical riches around me of milky-blue gentians, royal-blue harebells, glistening edelweiss, dark little orchids and garnet-bright sedum, watching the trickling water of a brook, and replaying last night’s music in my head. And if you move quick you can do this yourself before next Sunday.

It was partly as penance for having missed the previous evening's Czech festival that I arena-prommed for last night's Moravian finale, to be happily strafed by the nine extra trumpets of Janáček's Sinfonietta.

This week’s reviews include a generous Liszt anthology played by one of the 20th century’s most fondly remembered pianists. There’s a reissued box of Beethoven symphonies performed on modern instruments by one of the classiest European orchestras. Heading further north, we've a repackaged set of Sibelius symphonies with some essential extras.

Profound experience of 2010? For me, unquestionably, portions of the great Russian pianist Elisabeth Leonskaja's first-time journey through all the Schubert sonatas at the Verbier Festival. I was lucky to catch three out of nine recitals, and to talk to her about Schubert. I'd have been happy to listen again to any of those extraordinary works - all 19 are loveably idiosyncratic - in London. But this was a strand of unusual radiance I hadn't caught at Verbier embracing, as ever, Schubert's deepest sorrow in a late piece served up as prelude, the meltingly beautiful A-major Sonata D664 and that Olympus of Schubertian difficulty, the Wanderer Fantasy.

There's a parallel, of course, between the way Schubert can subject a simple-seeming phrase to endless, discreetly emotional harmonic tweaks and Leonskaja's unfussy evasion of simple repetition when faced with the same idea. And we do hear both Schubert's variations on the opening unison theme of the D915 Allegretto in C minor and their reiteration an awful lot. A delicious lot, to be precise: Leonskaja follows the great source of so much of her inspiration, her mentor and duo partner Sviatoslav Richter, in observing all repeats (his response to a student who didn't, which she quoted expressively to me in the interview, "You don't love Schubert?", seems as good a response as any to false economy). And quite apart from the expressive differences she makes in the repeats, there are always long-term gains.

Take the glowing A-major song of the D664 Sonata's first movement (that Schubert composed it in his early twenties is a miracle in itself). You may even begin to feel it's creeping back once too often - though you will never lose concentration as a listener when Leonskaja plays - but then comes the benediction in the coda, stilling and sublime: the Lied's arpeggiating accompaniment becomes a chordal blessing. Without that longer span, it wouldn't have half the impact. Nor would the shorter, unrepeated but never emotionally lightweight Andante, shifting subtly into unexpected regions. And Leonskaja's epic-lyric balance then sends the Allegro finale soaring, swooping and waltzing into relatively clear blue skies.

All this held the listeners captive, with barely a shuffle, for the first 40 minutes. There was the same connection between intermezzo and sonata, and between the movements of the sonata, with the audience held rapt by Leonskaja's effortlessly profound musicianship, as we'd witnessed, spellbound, in the Chopin recital of 2009 that first made me realise this was one of the few great pianists left after Richter.

Quite a different cradling of life's sadness comes in the day and night of the Wanderer Fantasy. It's a daunting challenge in any programme, and it did mean a jolt from the more private Schubert which Leonskaja seems to understand better than any living pianist. But she is also a comprehensive stylist, with the weighty orchestral pianism of the Russian school keeping bass lines dauntingly clear among the welter of notes. Not that she hits every single one of them; nor did Schnabel, Cortot, Richter, Gilels or many of the other piano titans. But like them she keeps a magisterial sense of where we're going, and the forceful fugue really did crown the work.

Apt, too, that after this Leonskaja should have chosen to end with a composer impressed by the flashier side of Schubert's early Romanticism - birthday boy Franz Liszt, and a typically eloquent song without words, his "Petrarch Sonnet No 104". But I have to say my heart was still with Schubert in tenderest A-major mode.

• Read theartsdesk Q&A with Elisabeth Leonskaja

Overleaf: Leonskaja plays the finale of Beethoven's "Tempest" Sonata as a concert encore