IMHO an embedded DSL (eDSL) helps to close the loop somewhat. At least you're writing your "configuration code" in a real programming language, while still keeping the configuration separate from the main application. It addresses most of the issues the article points out regarding custom DSLs: no/limited debug capability, lack of tooling and IDE support, unable to write the same style of code used in the application. Of course, it helps if your main language has good support for eDSLs, since not all do.