When I think of crossover, I think of Freddy Mercury singing operatic stuff with Montserrat Caballe. Lovely. But Freddy had a natural aptitude that most rock stars just don't.

I sing in a folk chorus in Toronto with a classically trained conductor ... and I have to say that we cannot produce the folk sound we aim for *as a chorus* without the vocal training we get in rehearsal from Isabel Bernaus. If we do not all produce the same vowel in the same manner at the same time with the same consonants in the same instant, and for the same duration, we can make a muddy mess of (for instance) "Shenandoah" or "My City". But there are 70-odd of us. We can't sing "My City" the same way Grit Laskin does.