It depends on how it is used in play. I rarely find the discovery of physical geography to be all that compelling in play. Not saying it never can be for me, and certainly I know others may enjoy it... but that's not what I generally enjoy about play.
Despite it history and association with sandbox campaigns my campaign doesn't do much in the way of exploration of geography. Instead what happens is this. On the left is what most players adventuring in the City-State region know about Dearthwood. A green blob with some major geographical feature that is home to several orc tribes. One the right is my master index to what in Dearthwood. Nothing exists there in isolation so are discoverable as in roleplaying with NPCs gaining information. But except for a handful no NPCs has a map like on the right this in-game.
The last half dozen entries of the
gaming ballistic log are an excellent account of how this plays out.
I mentioned my campaign of Spire earlier in the thread... how 75% of play took place in one district of the city. The geography was not unknown to the players... their characters were all raised there, that's why they were chosen to be involved by their minister. So geographical knowledge was assumed. They knew the established locations on the map, and because the map we used doesn't detail every single building, I granted them a lot of leeway in asking about other locations.
You should appreciate this then.
Plus, my last Majestic Wilderlands campaign was centered solely on the City State of the Invincible Overlord, except for the last half-dozen sessions.
The social network of the district, on the other hand, was something they did have to deal with. It had been several years since the characters had lived there, so they were unfamiliar with many things. Having said that, I didn't make them hunt and peck for a lot of it... I just shared it with them as it became relevant. For example, crime is a huge factor in the district... so I let them know the three major factions in the criminal underworld. I didn't hide that from them... why would I? It's common enough knowledge that I assume they learn it.
Part of deciding what is plausible is considering what is common knowledge or not. Plus
That assumption of competence extends to what characters know about the setting. And its application to my setting has shaped by the feedback from my players about what their character would and wouldn't know.
Take for example, your three major criminal factions. While their existence would plausibly be common knowledge many details of their organization would not in a world where they existed. Why their existence be common knowledge> I am assuming they have large memberships and a history in the city. The ripple effects over time would ensure some amount of awareness would exist. However because they criminal organization there are many things they would keep secret despite that.
In my City-State of the Invincible Overlord there are two thieves guild the Brotherhood of the Lion and the Beggars Guild. Nearly everybody who adventured in CSIO knew about them and I happily expanded certain details when asked. But many details I didn't divulge because the character would not plausibly know them.
However for the campaign where everybody was a member of the Brotherhood of the Lion, the players knew far more than normal about the criminal underworld and I would supply more details when asked.
So what the deal with the asking part? Players are people, some want to soak in all the information while other don't really give a crap, most are inbetween. What the players know is that if feel they need to know some background detail, all they have to do is ask. Also I do this.
I have three categories of information.
- Stuff that is common knowledge that is available at any time.
- Stuff that require some area knowledge in which case the player needs to make a area knowledge check.
- Stuff that is not plausible is known to the players or those with area knowledge. The bulk of these are the personal plans of NPCs and the goals they set out for themselves.
This reflects how information works in life.
As you described it, it seemed that your idea of realism or setting consistency or plausibility is what mattered most.
Setting consistency. Realism enters the picture if the elements of the setting are meant to be realistic, like Harn. I would not consider realism in the same way for GURPS Discworld as I would do for GURPS Majestic Wilderlands.