“Only in recent years has Handel’s piece — composed in 1741 and long associated with Christmas, though it was intended, one biographer wrote, ‘as a timely thought-provoker for Lent and Easter’ — been interpreted by choreographers. Schroeder points out that it has often been difficult for dance companies, including hers, to find willing collaborators among classical musicians, many of whom believe “Messiah” is strictly for voice and orchestra.”