Tony Bennett came to the ACC in 2009. Notre Dame joined the ACC in 2012 when Mike Brey had been there for 12 years.
Both coaches have developed philosophies that rely on developing young players and getting them on the court later in their careers. When you think about guys like Jay Huff or John Mooney, they kind of illustrate the point and value of the system.
Moreover, both coaches have done this, and generally very well, as many schools have accepted the one-and-done philosophy or at least the idea that players are gunning for the NBA and want to get there as quickly as possible.