“In what are expected to be the most bitter contract talks on the Great White Way in recent history, show producers are pushing to eliminate a longstanding union rule that compels Broadway theaters to hire a minimum number of musicians, currently 3 to 26, depending on the size of the venue. And vowing that the shows must go on in the event of a strike, producers are turning to a high-tech offshoot of taped music known as virtual orchestras, capable of simulating the subtle variations of tempo and tone in live music.”