I think the key phrase is "some of the...". Both major airline operators that I flew for rarely flew two captains together on a line flight (for obvious cost reasons) although I've never seen or heard of a two captains restriction. There could be lots of reasons that your operator, atakacks, actively avoided this, not necessarily because they're all megalomaniacs - as I think that you and RoyHudd are implying. Let's just wait for the report?