I have a RadTabControl in my control set as follows:
Based on the documentation RadTabControl should use ItemTemplateSelector to pick the actual DataTemplate used to display item in ItemsSource. So it picks the ContentTemplate for RadTabItem from there. It seems that there is a bug with it as it picks the DataTemplate but uses it as the HeaderTemplate for RadTabItem not as content template. Content wrongly displays the Type name of the item in ItemsSource.
Another problem is with DisplayMemberPath. It should use DisplayMemberPath to display the header of RadTabItem when ItemTemplateSelector is used but instead I get a error that I cannot use DisplayMemberPath when I'm using ItemTemplateSelector.
So clearly it works differently than the documention says it should work.