Tankengine, thanks for the info how it's done in QF.
I do agree with this practice and myself do the same thing when
operating as the second captain.
The problem now that confuses this whole thing is that other airlines and country's in the world all do it differently. Same do it QF way, while others
do it another way. Actually in the EASA regs, it does state that whole ever sits in the left seat and acts as commander when the official PIC is off deck
having rest, can log PIC. Because that person is now making all decisions for that phase of flight.
So this is where it gets stuck!
You have pilots claiming they have PIC hours on an aircraft where they were not the official designated PIC
Just wish the whole world was standardized in this issue of logging hours.