“A few of us, though, have been living in such privileged conditions that it is still a shock to realize that live music is negotiable. This shock, I know, is illogical… [Yet you] need to be a regular dancegoer to know quite how much difference a conductor and orchestra can create between the same cast’s performances of the same ballet on Wednesday and on Thursday. Where there is taped music, sooner or later you’re likely to see taped dancing.”