This drill is from Breakthrough Basketball. This drill has 3 main purposes. It teaches players to 1) Quickly apply full court defensive pressure after making a layup. 2) Make layups in transition. 3) Get open when you are being guarded with a lot of pressure. This is one drill that works on all 3 of those aspects of the game. Drills that involve more than one skill are so much better for player development. Practice time must be as efficient as possible.