787 What a lot of fuss over nothing at all! Many airlines have done it for years. You simply swap seats and act as an FO for a leg, then swap back again the next leg. What need for the sim etc. required to accomplish that tricky little job?
I sometimes feel that anything out of the ordinary in this bussiness just HAS to be questioned, ridiculed, rubbished and objected to simply because it's there! Sad really.