He's not playing halfback, Norman is.
Prior to yesterday we played with split halves, with Norman and Sandow getting roughly even number of touches (about 50 each). Yesterday Norman handled the ball 70 times to Kelly's 48, and 10 of those were kicks (Norman kicked five times).
Kelly is very much in the team to play the supporting half role. All he needs to do better than Sandow is tackle. Plus he's better at kicking short.
No team in the NRL has both halves dominate the stats. One has to be more of a lead than the other.