If we think of Drag Refactoring as a commit, then the target page might indicate that this structure already exists and the commit could be reverted. Target page could show the occurrence of identical subpatterns.
We continue to suffer under one poor choice I (Ward) made early in the project: drag refactoring. This was a design goal. I had hoped that a carelessly organized set of pages could be drag and drop refactored into a better design.