I'm struggling to find references but this is a fairly well established phenomenon, called "risk shift" I think. A small group accepts a greater level of risk as a "team" than any of the individuals would on their own.
When I flew as a co-pilot on corporate jets it was always a great relief to think that the guy in the left seat had the ultimate responsibility.
Even though the co-pilot seemed to do all the work
while the captain sat there looking all important it was very much you are in command if we crash and die at least its your fault
My first flight as Captain was a mixture of elation " this ship is mine", puffed out chest etc. to absolute dread that the guy in the right seat was relaxed at the thought that you are boss and if we crash its your fault
But once you fly as a Captain you are a Captain. In that left seat it doesnt matter who the hell is in the right you are the Captain and when the guy in the right knows that you are the CAPTAIN
if you get my gist.
Pace