code: protected DOMOutputElement createAndAttachChild(Element element)
      {
          if (mRootNode != null) {
              mRootNode.appendChild(element);
          } else {
              mElement.appendChild(element);
          }
          return createChild(element);
      }
docs: Simplest factory method, which gets called when a 1-argument
  element output method is called. It is, then, assumed to
  use the default namespace.
  Will both create the child element and attach it to parent element,
  or lacking own owner document.