The VSTS User Education team has posted a draft of updated documentation for the topic "Moving Team Foundation Server From One Configuration To Another" for public review.  An undocumented change to the RenameDT command essentially invalidated the docs we had, so this version should clear the story up.  If you're planning or currently working through one of these move scenarios, please check out this new version of the documentation for the latest steps and give the UE team feedback.

Read:  Draft Documentation Update for Moving Team Foundation Server from One Hardware Configuration to Another  (VSTS UE Blog)