Those 52 % of you in the "sometimes or more" category:
Are you guys all running Adventure Paths or at least some sort of metaplot-driven-game?
Yes I'm currently running a sandbox with the STK and ToD backdrop. The characters are free to pursue the metaplot should they so wish (they currently are) or veer completely off course and ditch it entirely. One character has a reason to travel to Sigil and another has the goal of hunting and stopping an individual from resurrecting a dead god.
Are any of you using 'Success at a Cost' (DMG 242) and could you see the following action resolution handling occur in your game?
I find I might use either scenario and yes I do use Success at a Cost.
In scenario (a) if the location of the Dawnmoat was predetermined then the character would have to try discover it another away (if possible).