EzekielRaiden
Follower of the Way
Exactly.It means the GM's view of common sense.
This is why most RPG worlds make no sense politically or sociologically, because - notoriously, I would say - most people's political and sociological common sense is not that strong. To me, that seems to come through in the actual discussion of the bribery scenario: why would the worlds of D&D have officials who follow the norms of contemporary European and North American bureaucracies, as opposed to the norms that are far more common even in most contemporary bureaucracies, let alone among historical officials?
But it can be an issue when it comes to other domains of "common sense" also. I've seen discussions of athletic endeavour that make no sense - eg I am in my 6th decade of life, and in the past two years I have been able to run a half-marathon, not in any great time but with no ill effects other than pulling up a little sore the next morning, after doing 4 training runs (of 11 to 16 km) in the few weeks preceding the event. So that sort of performance sets an absolute minimum baseline for what ordinary people who live physical as opposed to sedentary scholarly lives can do.
Once, in a convention sci-fi scenario, the PCs (one of whom I was playing) were stuck in an installation where the oxygen supply had been cut off. So we had only the oxygen present in the base at the time the supply was cut off. One of the players was a chemical engineer, and so was able to quickly calculate that we had enough oxygen to last some hours, and we planned our actions around that. But then the GM imposed his "realistic" conception of how long we would have - it was expressed in minutes or maybe tens of minutes, and so our plans were hosed. Naturally enough, that left a pretty sour taste in our mouths as players.
"Common sense" is often neither common to all participants in a game, nor particularly sensible! And yes, I have found very specifically that the "common sense" for athletic ability is often wildly off base and far, far short of what is actually achievable IRL. I call it the "guy at the gym" problem: as you say, most nerds live "sedentary scholarly lives" and thus their standard for what is achievable by practiced, athletic people is skewed heavily toward "what a guy at the gym could do", not--as would be much more fitting--what a Navy SEAL or Green Beret can do, let alone the kinds of things an "ordinary" person can achieve in an openly fantastical world where flying bus-sized lizards can breathe explosive halitosis on such a so-called "ordinary" person and they...shrug it off as little more than a slight sting.