Being able to handle the basketball comfortably with either hand can add a lot of value to a player's game. It gives them the ability to handle pressure better, make dribble moves, and penetrate to either side. This two ball basketball dribbling drill is going to work on helping the player develop both hands at the same time, and also give them confidence to make a move with either hand.
The goal of this drill is to force the player to get out of their comfort zone. That way when they get into an actual game situation, they will be a lot more comfortable handling the basketball. Also, by having to follow the leader, the player must keep their eyes up and see what is going on while they dribble the basketball. That translates into a game situation where a player has to read the defense, and also set up the offense.