Why does de Mille’s choreography seem so dated now, while Fosse’s still looks as fresh and provocative as ever? It’s particularly puzzling considering that de Mille was the more revolutionary of the two. She created a startling new approach to integrating dance into the musical via character development, and established the standard for the widely imitated (and later much-parodied) “dream ballet,” an expressionistic choreographic sequence probing deep into characters’ psyches. Fosse’s great contribution to Broadway dance, on the other hand, is largely limited to his creation of a compelling physical vocabulary,