Just for clarification I was talking about switching seats on the ground. If you only have one tiller the co-pilots need to be aware of this option. Stopping on the runway or on a taxiway may well be better. It depends on the circumstances. With American in Syracuse the co-pilot intended to stop on a taxiway. But the responders did not have steps so he carried on to a gate. Thanks to Deptrai who has meanwhile covered some things I would otherwise have mentioned.