Allow "Export FBX" to export smoothing groups?

Similar line of enquiry to this thread: Allow StaticMeshEditor to change the source mesh Pivot - Unreal Engine Forums

It would be great if when exporting fbx meshes from the editor, it actually exported the smoothing groups too. Currently it’s not possible to import meshes into the editor, then seamlessly export them back into your 3D package (particularly 3DS Max) - because information is irreversibly lost.