Would have to agree with Flying Clog!!! What happens when it's time for an F/O to upgrade to left seat?? In my company an F/O is more or less concidered a future captain on "line training" and shares pretty much all duties with the captain (except for some paper signing). The F/O is also allowed to initiate an abort, during the aborted T/O procedure the F/O then becomes PNF. I think this system workes excelent.