Ref the 'Zammo' post, just a sad flashback moment tbh.
I am, however, concerned by the CRM aspect espoused by a couple of posters in this thread. One would hope that your professionalism and inherent CRM principles mitigates any perceived authority gradient issues. As for the end of season demotion, if the guy knows the score, there should be little to beef about. If anything, it should add considerable value to their FO role as they will have had that brief insight to the 'loneliness of command'.
In a previous lilfe, we often flew with 2 skippers, one of whom would be designated FO for the tour. Admittedly a fairly close knit set-up where we all knew one another, but there were never any such problems. Gadzooks, we even swopped seats!
Still, the CAA aspects etc not really my bag, so I shall retire....bonsoir.