Johnson shined as a recruiter during his time at Indiana, making him a hot commodity on the coaching market. Maryland and Virginia Tech came after him initially, but a job on Pitino's staff was one Johnson ultimately couldn't turn down.
During his tenure, Johnson helped Indiana land several recruits from the East coast, the area he's from. Johnson got Indiana in the door with Troy Williams, Stanford Robinson, Noah Vonleh and Robert Johnson.
But it's important to remember, Tom Crean ultimately landed all those guys. Kids don't go to a school because of the assistant coach. They go, ultimately, because of the head coach.
Sure, losing Johnson isn't the best news, but it isn't the end of the world either. Crean is and always has been a solid recruiter, and that won't change now. The rivalry with Louisville, well, that could heat up a bit more. The two teams play each other in the Jimmy V Classic next year.