In reply to tattoo2005:
I went to a Royal Ballet performance of Twlya Tharp's 'Mr Worldly Wise' 11 years ago, Darcey Bussell was the principal was injured that day so we got her understudy, Benazir Hussein, who seemed (to my untrained eye) perfect.
More smugly, I singled out the minor role of "Carrot" (a dancer in a big carrot costume, playing a carrot) as having a particular grace and presence. It was a young Sarah Wildor. Maybe I should become a ballet talent-spotter