Honestly, it was a 10 second example
I tried to give you sympathy XP for pouring over the entrails of your 10 second example, but apparently can't yet.
If the map of the city is drawn up, the path decided, and the map considered part of the setting, it's changing the fiction (to my group).
<snip>
If I have a map as GM, it's now set in the setting. I will not be changing it for convenience's sake.
That said, the players don't see my full map assuming I've even drawn one. I'm perfectly willing to change things if the group gives me a better option than the one I have in mind.
My approach is much closer to Mort's. I tend to do the same with NPC motivations, as per
this quote from Paul Czege:
I frame the character into the middle of conflicts I think will push and pull in ways that are interesting to me and to the player. I keep NPC personalities somewhat unfixed in my mind, allowing me to retroactively justify their behaviors in support of this.
Of course, once it's been accepted by everyone at the table as part of the shared fiction, then it is settled unless it is somehow unsettled by agreement (a character within the fiction does something to change things in the fiction, or something goes wrong at the table and we all agree to a retcon, or whatever).
I think that's going to be the situation in most D&D settings though as there are no real mechanics for players to truly (no DM filter) take control of the narrative from the DM.
This comment isn't intended as contradiction, but reflection and elaboration. Arguably in D&D, if the players - by application of the action resolution mechanics for their PCs - reduce a monster or NPC to zero hit points, then the GM is obliged to narrate that the NPC or monster is dead.
And a similar example came up in my game a couple of months ago with a skill challenge. After
this episode, the players had won a skill challenge, which in effect meant that their PCs had taunted an enemy - whom they had run into at a formal dinner and were therefore precluded from confronting directly - into attacking them, and therefore betraying his true colours in front of all the assembled NPC worthies. In a subsequent session, I narrated some conduct by some NPC which only made sense if the allegiance of the PC's enemy had remained ambiguous after the skill challenge. One of my players reminded me of the skill challenge success, and that the success meant that the true colours of the enemy
had been exposed. I accepted the corerection and redescribed the situation appropriately.
I don't know where you (or others) put this on the spectrum of players' narrative control, but it felt like it at the time (at least to me as GM)!
that was presumptuous of me. I apologize.
Thanks, though there's no need to apologise! It's an internet forum - everyone's doing their best to work out what the hell these other strangers are banging on about!
I'm near-positive that after your initial post saying you'd use mechanics to resolve this, I quoted you and posted that I agree. Why you assume I wouldn't use mechanics to resolve this is still exceptionally unclear to me.
Well, in the reply to that post I did say that I was going to use your agreement to wedge you, but then qualified (in paranetheses) that I wasn't entirely sure how you would handle it, and so maybe wasn't wedging you but agreeing with you.
I think that in a subsequent post you said that autowin for the NPC was OK, and to me autowin implied "no mechanics, just GM fiat".
One interesting point in the neighbourhood is this: you have said that you would have the NPC do a Streetwise (or whatever) check, and if successful take the shortest route. The players could do the same for their PCs, and then if they succeeded too the chase would be on.
So each check is resolved not as part of a conflict, but as an independent factor in the situation. I personally prefer the BW way of doing it, which is that if the players win the oppposed check then the NPC failed - and that failure can be narrated in various ways that don't have to immediately reflect the PCs agency in the gameworld (for example, losing the opposed check could mean the NPC gets stuck in a street fair, even though the players winning their check for their PCs does
not correspond to the PCs somehow setting up a street fair). Skill challenges are meant to be handled the same way in 4e (which is pretty obvious, I think, from the structure of the mechanics, and becomes obvious if not expressly acknowledged in the example of play in the Rules Compendium). When the PCs fail on a check, the GM is free to narrate some sort of complication or adversity which isn't necessarily, within the gameworld,
caused by the PC failing at something (eg a player failing a diplomacy check could mean that, although the PC was very coureous etc, as s/he was speaking a bird flew overhead and crapped on the NPC's cloak, irritating the NPC and thus negating the PC's attempt to influence him/her through no fault of the PC's).
But this isn't a point about narrative control by players, but rather the introduction of a metagame element into action resolution.