I would recommend allowing for tabs in a tabbed pane to be draggable in regard to re-ordering.
I couldn't work out how to re-order the tabs in an intuitive way... hence why a better metaphor for re-ordering is required.
[Search keywords: reorder re-order re-ordering reordering change order position placement tabs tabbed tab pane]
Changing the tab order works very poorly. It often happens that the tab appears elsewhere than we wanted. It is very annoying. This "bug" is since I can remember in 6.x and 7.3.
I noticed that "bug" occurs at the time when we opened about 10 or more tabs. Then the problems begin.