2 Captains together is no problem, our company use it to achieve greater flexibility. To us it is not unusual, nor a problem.
The only proviso is that the captain in RHS has been checked in the RHS in the sim, this includes single engine go-around and single engine landing. Normally LHS hogs the flying and is designated as PIC. The RHS captain gets captain's pay and allowances.
It is not exciting nor dangerous, so no exclamation marks.