Thanks for the comment.
This article talks more on concept rather than implementation.
There is no harm using Spring Framework and other open source framework readily available in the market.But we need to know what is there behind those Framework and how it suits in the organizaton where it's going to be used.If said organization is required to utilize only 40% advantages of Spring Framework,then probably we need to think twice before choosing the Spring framework as it has got its own learning curve and overhead of so many classes may not be used in said implementation.
The advantage of using home grown component has got some initial effort for conceptulization and design and development.But it would be(should be)
conceptualized considering the organizational need/requirement.But once it's done,it will be easy to use,maintain and enhance.