Jason it is possible to approve an article without creating a new version of the article, which is what is most likely occuring for your editor.
On the approval screen instead of Editing a version, if you were to preview the version that is waiting for approval, by clicking on the article name/link, then click on the "change approval status" link in the admin menu above the article.
From there the editor can add any notes and change the status of an item, without creating a new version.
Does that help?