He is a bit over the top. Use best practices, but dont create an interface for only one class dont create an abstract class for only one subclass, dont create

He is a bit over the top. Use best practices, but dont create an interface for only one class dont create an abstract class for only one subclass, dont create a data only class where a HashMap will work. All this extra code has to be maintained by someone. In fact the essence of maintainability is to have less code.