First, sorry for the delayed reply.
I realize that the drag/drop is acting inconsistently, because the TreeView shows different drag/drop cues.
There are is a way in which you can give feedback:
The in/before/after cue can appear as part of the drag cue so it will say "Drop Item A after Item B". This approach will involve no changes to thee TreeView.
Currently the DragDrop cues are part of the TreeView (not TreeViewItem) and cannot be shown/hidden easily.
We will consider making the TreeView cues publicly accessible.
Unfortunately I cannot think of a better solution right now.
the Telerik team
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