Petersburg, the principal conductor of the London Symphony Orchestra, and a guest conductor everywhere else does not solve the question that has puzzled music lovers for two decades: How does Gergiev do everything he does?

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But that alone does not rule out introduction of a fully-fledged guest conductor system elsewhere.

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Harding, who has been principal guest conductor with the LSO since 2006, will also conduct a Prom with the Mahler Chamber Orchestra on 30 July, where he holds the lifetime post of Conductor Laureate.

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