Virtually every system that allows such adjustments (through some sort of point mechanic that allows the player to add to their roll or to re-roll a given die) requires the player to apply the adjustment before they know the outcome of the roll. The player is asked to gamble that A) the adjustment enabled by the resource will increase their result sufficiently to succeed, and B) that their original result was insufficient in the first place.
When I started working up the Stunt mechanic for DPoNI, which I originally got from iwatt, I used the same thinking. You could apply bonuses to your checks based on your skill ranks, if you got creative and gave me a good description. But folks didn't use the stunt rules all that often. Usually they'd forget in the heat of battle, or just shrug and hope for a good roll without the bonus.
I hadn't gotten the rules right. This was a cool idea, something very much in line with the feel I want for DPoNI, but my players weren't naturally gravitating to it. I took out a few of the other optional rules I'd implemented, but stunts remained a little-used feature.
It turned out the best way to get players to consider stunts was for me to suggest them -- and this started happening AFTER the die roll. If somebody had missed by only a little bit, there'd be a scramble to look over the character sheet and find some over-looked bonus that might apply. Stunts fit the bill admirably. Because they work as a static bonus, rather than a re-roll, they represent sort of that little extra effort that a character makes, using their existing skills, to just do a little better. And because you can apply them after discovering your roll wasn't quite enough, you don't need to keep track of every possibility while making your decisions -- you can discover possibilities afterwards, when you know you need them.
It means characters in DPoNI are a little tougher than standard True20 characters. They'll make successful rolls some 10% more often, depending on their level. And that's okay. DPoNI is meant to be more about coming up with cool stuff to do rather than managing resources and surviving (once again, like ALWAYS) by the skin of your teeth.
I tend to play more of a style where a player says what they want to TRY and do, and then makes a roll, the result of which tells us how WELL they did. So the actual narration of the event simulated by the die roll naturally comes after the roll is made and success is determined. The Stunt bonus, in this context, is more a function of the narration than the attempt. It works like this:
Player: "I attack! I get a... 14."
DM: "Oh, dear. You need at least a 16 to hit this guy."
(player looks over character sheet and notes she can get a +2 stunt bonus from her Acrobatics skill)
Player: "Okay, but I'm using my Acrobatics."
DM: "Okay, you'll just barely hit if you can do that. How are you using Acrobatics here?"
Player: "I run up the side of the cavern, somersaulting backwards and landing behind him, catching him just off-guard enough to skewer him before he knows I'm there."
DM: "Sold."
When a player rolls well, often the satisfaction of the roll is reward enough -- not all players feel a need to narrate something cool at that point. And likewise when a player completely botches a roll -- they're cranky and frustrated and not inclined to jump in with a bunch of creativity.
But nothing spurs creativity like the knowledge that if you can come up with something, you can snatch victory from them bitey jaws of defeat. So what do you think? Is this a reasonable way to run things? Does it require too much adjudication on the DM's part? Should NPCs get the same benefits?
Fish photo: Gavin Mills