One thing you can always count on with Mark Morris is great music, always performed by top-notch musicians, always live! You could come for the music alone, with the dance as an added extra. And his choices are almost never from the well-known stuff. The latest presentation by the Mark Morris Dance Group at the Moore Theatre was no exception. This time he gave us a brilliant trio by Johann Nepomuk Hummel, 'Piano Trio No. 5 in E. Major, Op. 83,' and a dark, original score by improvisational jazz trio, The Bad Plus. Two more different works would be hard to find!