Ah that fight was sex. I actually beat Desann fairly quickly(set on Jedi/normal difficulty).
I had it set on strong style. And kept on using Force Push, sure you'll mostly get, "You dare push me?!" But once in awhile he'll go flying. It's then you run in and VMM! I finshed him that way in a couple of shots(surprised me in a way). All the other while I was running.