“Some of her famously quarrelsome relatives doubtless regard Katharina Wagner as little more than an inexperienced blonde harpy luring the Wagner family honour on to the rocks. But this week the great-granddaughter of Richard Wagner took a decisive step in the battle to take control of the composer’s most prestigious legacy: Germany’s Bayreuth Festival. When the tantrums and walk-outs started, it was the 26-year-old Madonna fan who saved the day.”