Imaculata
Hero
At a RPG table, in the situation being described in the posts above, the players give rise to an idea - our PCs find some sect members at the teahouse - and they suggest that that idea should be an element of the fiction that is being collectively created at the table. The GM then decides whether or not that idea actually does become part of the shared fiction, and communicates that decision to the players by telling them what it is that their PCs find at the teahouse.
I'm not sure if I've ever played in a group that plays this way. In all of the games I have played, or been the DM for, the DM already has an idea what is at the teahouse. Any suggestions made by the players may, but won't necesarily change his preestablished ideas.
For example:
My players are currently inside an underground cathedral, where they see evil monks carrying a coffin around with their dead high priest. They are about to start a fight with them, which will be the start of our next session. But before the last session, one of the players said "It would not surprise me if that high priest isn't entirely dead". Of course I know the answer to this, and whether I change my mind is entirely up to me. But I don't generally change the fiction based on ideas that my players randomly spout during the session.
If the highpriest was intended to be still alive (or undead), I won't just change it just because my players correctly guessed my intentions. Nor do I now make him alive, when he was originally dead. I suppose I have until our next session to change the fiction any way I like, but I usually don't. Not that I don't appreciate player-input, but I kind of like the idea that what's there is there, and what isn't, is not. I don't mind not surprising my players, when it was my original intention to do so. Because guessing a trap correctly, can also be satisfying to the players.
I get the impression that none of the DM's that I have played with, change their mind like that either. Of course, this is merely my impression, I didn't ask them.