Learsfool, that statement you're referring to, was made in jest more or less, but it was in regard to "improvisation". Actually I witnessed shows that were improvised night after night, and I found it unbelievable.
Equally unbelievable are "pit musicians". Beyond the fact that each musician played several different musical instruments, was how they played written music that sounded like improvised jazz; that boggled my mind; and I forgot, this music had to correspond with action going on, in a play on stage.
Could you elaborate on these musicians?
Enjoy the music.