I can't have imagined that there wasn't one; it helps to define the subject of discussion.Dr. Awkward said:Okay, I think we're zeroing in on the disconnect here.
It can be if the players are questioning his cards, and the DM says, "Quit questioning me about what I'm holding, get back to the game." This is problematic when the players think the DM is changing his cards to counter what the players have but he actually isn't.I don't really think of the DM's privilege as the only member of the table to play with his cards in his hand, rather than on the table, to be an example of DM fiat.
If you disallow this kind of DM Fiat, then the only way for the players to make sure the DM is "playing fiar", is to force the DM to reveal his hand.
Yes, the DM should have a reasonable explanation for why his NPCs do the things they do. And I agree that no DM should have to show his notes to the players; I find the notion of players auditing the DM offensive. So in this regard, a DM using Fiat to say, "I have a reason, so back off; who's turn is it?" is perfectly acceptable.Essentially, the way I read it, DM fiat is when you break from the ability to honestly show your DM's notes to a player for checking. Not that I think any DM should have to. But an indepenent observer should be able to ask you the question "why didn't his diplomacy check work," and get an answer that would satisfy a reasonable player.
DM Fiat to say, "I am unclear as to this particular rule I didn't expect, so I'm going to rule it this way for now, and decide after the game what we'll do for now on." is also perfectly reasonable.
EDIT
Schweeet! 2000 posts!