As that cheeky geezer Nige might have said, not a bad effing evening, even allowing for the long-winded jazzy stuff. How often do we have the chance to savour Elgar's Violin Concerto and then hear the same soloist work his way through a set of jazz-rock numbers? I suppose that the next logical step would be to set about playing the Elgar on an electric violin. (Memo to starry-eyed Proms organisers: that was just a joke. Please, please don't take me seriously.)

In all honesty, to this jazzer's ears, the orchestral part of the evening proved much more engaging. While Kennedy's impassioned, even reckless performance created the illusion that the Elgar had come direct from the composer's pen, the late Prom - featuring the violinist's Polish band - had a distinctly secondhand aura to it. When the guitar hero Jeff Beck made an unexpected entrance midway through Hills of Saturn the penny dropped: this was the kind of music that would have set hearts aflutter in 1968 but which now sounded undeniably tame.

There's still much to admire in Kennedy's efforts to open classical listeners' ears to other traditions, and to jettison some of the starchier aspects of concert hall protocol. Yes, the swearing was juvenile, but the unshockable Promenaders chuckled indulgently and the conductor Paul Daniel was happy to play along with the violinist's banter about the late arrival of the concerto score.

It was just a pity that there was not more of a shock factor to the late show. Kennedy's latest recording - the self-mockingly titled A Very Nice Album - drifts amiably enough through some undemanding, Latin-tinged electric jazz and folk-rock without ever threatening to catch fire. The same was true of the live version, the leader delivering extended solos whose formulaic phrasing and fuzzy tone often left you wondering why he didn't simply hire a moderately talented guitarist instead. His passion for Jimi Hendrix was given full rein on the hard-driving Third Stone from the Sun. While the guest singer Xantoné Blacq emerged from the wings on the upbeat Carnivore of the Animals, his contribution was almost entirely inaudible.

Tomasz Grzegorski made a few pithy interjections on tenor and added ominous touches on bass clarinet, but the rest of the band was content to sit in Kennedy's shadow. I had hoped that he would think again before trying to reprise the painfully unfunny, strangulated vocals of Boo Boooz Blooooze, but he plunged ahead regardless. Once again, the audience refused to be shocked. What's wrong with these classical music lovers? Don't they know they're supposed to be square?

Editor's choice

• The 100 Best Films of the Decade
• 70 facts you didn't know about Marvel
• The 50 Biggest Movies Of 2010