Chroniclers of the musical theater have been around for years, collecting pictorial surveys, librettos and scores, and recording the careers of various theatrical celebrities.
When it was realized the importance of dancing as a tool for character development and plot advancement, famous director-choreographers began to emerge: Jerome Robbins, Bob Fosse, and Gower Champion.
This was definitely evident in West Side Story when Robbins allowed the choreography and the intense, adolescent passion of a teenage boy in love to move him.
When Robbins abandoned commercial dance to pursue a career in choreography with the New York City Ballet, Bob Fosse took up the cause and argued the case for director-choreographers with shows like Sweet Charity, Pippin, Chicago, and Dancin'.
Fosse had a talent for manipulating, tampering with, or otherwise reconstructing the contribution from writers in order to make the material serviceable to his staging and choreography.