Russian mezzo-soprano Olga Borodina has developed quite a reputation as one of her generation’s most opinionated divas. Two years ago, she walked out on conductor Antonio Pappano and the UK’s Royal Opera House in a dispute over director Robert Wilson’s approach to Aida, and just recently, she quit a La Scala production of Carmen when she discovered that the recitatives were to be spoken rather than sung. But her temperament seems to stem not from ego, but from a deep belief that there is a right way and a wrong way to approach music, and that she, as an artist, should not be asked to compromise her musical values.