FOs got left seat training when they were initially trained. I was never an FO on the airplane I am flying and I never received right seat training in decompression, emergency descent and TCAS maneuvers. Therefore I am not qualified to sit in the right seat.
I strongly suspect numerous captains have not sat in the right seat in years and is out currency to sit in the right seat without additional right hand seat training.
On another note the FAA is looking into EK application's to fly the A-380 to SFO. The FAA is finally concerned that the flight attendants are only getting 2 1/2 hours of rest on the ULRs which sometimes are 16 hours of flight time.