Hi DozyWannabe,
Remember that the rules state that the non-relief pilot is not to take control without the Captain's say-so under most conditions.
I've never heard of that.
PF / PNF can swap roles at any time - usually one crew member is allocated the pleasure of doing the take off and landing for his records. Unusually with this crew was their relative seat positions. The more experienced senior Co-pilot was not in his natural seat (Co-pilots occupy the RHS), and may have felt some anxiety about taking control and using his non natural hand on the side stick.