From the timing to the personnel, it seemed as though extramusical interests would dominate the first complete cycle of Beethoven's symphonies at the BBC Proms since 1942. Scheduled to end as the Olympic Games opened, the nine works that revolutionised the remit of orchestral music - shattering harmonic and structural conventions, describing the best and worst of humankind, proposing philosophical arguments in furls of woodwind, brass, strings and, finally, voices - were presented as a personal marathon for conductor Daniel Barenboim and the Arab, Israeli and Spanish players of the West-Eastern Divan Orchestra.