This basketball drill is going to work on the players ability to move up the floor at a high speed, and then make a dribble move without having to slow down. It is great for simulating transition and attacking a defender that is out in front and already set on defense. To add to the difficulty of this ball handling drill though, you are going to add a second basketball. The idea behind adding a second ball, is that if player can do a move with two basketballs in a drill, then they should be able to comfortably execute the move in a game situation with only one basketball.
Two ball basketball dribbling drills are also great for eliminating a players weak hand. The reason it does this so well is because both hands must dribble a basketball the entire time, and the player doesn't have the option of being able to switch the basketball over to their strong hand once they get in trouble.