Recently I left a comment on Philip Watson's thread on Google+ where he wondered whether players should know when their thief failed to hide. I said:
Consequences happen right after the result of the die roll is known. As a referee, I have have no “information advantage” and thus the question of unfairness doesn’t come up.
I was reminded of Courtney Campbell’s blog post On Skill Deconstruction: Why Roll for Resolution? He lists five reasons for rolling dice.
I’m trying to have thieves succeed automatically whenever possible. I’m going to opt for dice rolling when the conditions listed above are true. If the dungeon has wandering monsters, each failed roll to open a door or unlock a chest means one check for wandering monsters. If there are no monsters, we don’t need to know how long the thief takes to unlock the chest. It will succeed eventually.