The Utility of a Chunk

Once you chunk something, you don't completely forget about the internals. You just treat it as a black box so that you can conveniently manipulate it in your mind. I wonder if... I've thought about this a lot. What is the utility of a chunk or of a higher order concept or generalization? It's allowing you to work with it in the working memory and you get access to the deeper stuff if you need it, right? That's got to be really close to the truth.