"If I can't trust the guy to be a PIC with me onboard, how can I trust him to be PIC with the CEO onboard???"
I couldn't agree more.
I've always thought that ther term co-captain was an oxymoron created to serve ego. There should only be one captain on each leg. I am in no way suggesting that the other captain or first officer should not be used as a resource and be assertive if necessary but one leader is enough.
In my corporate days (oh how I miss them) I had the pleasure of working with a group, all qualified as captain and we swapped seats each leg and the left seat pilot served as captain. Never a problem.
In my present life, as a check airman I often find myself in the right seat as PIC because the person in the left seat is yet to be qualified. In that case, I am the PIC but I am not the captain. While I am responsible and accountable for the captain, that position along with all duties and decisions has been delegated to the trainee. I am simply acting as a first officer with the authority to intervene. (which almost NEVER happens)
Too many cooks spoil the stew!
CG