submit to workflow for published pages and posts

Take a look at the “Pro” version which comes with that feature. It essentially allows you to create a copy of the published article. The revision/copy flows through the workflow and then at the last step of the workflow, it simply copies over the revised content to the published article.

It allows you to define separate workflows for revisions and provides a way to compare the published content with the revised content.

This way your published content never goes offline, while allowing you to work on it’s revision.

Here’s the link – http://www.oasisworkflow.com/workflow-support-for-updating-published-content

Hope this helps.