It seems that the two don't get along. Code:
And I just generated a simple items source in the code behind:
The row reorder behavior code is taken from your examples. When trying to reorder rows, then I see the deferred mode adorner and the docking compasses.
This is not the only problem. Try reordering the rows... After few drag and drops (Usually a quick drag and drop), the "Watch" pane (where the GridView was in) will disappear (because it was removed from its original group and added a some group with no items).