Barely Success

So Tim and I have been looking through the Doctor Who RPG (which also uses a 2d6 mechanic) and they had an interesting concept about degrees of success.  A lot of points below the DC means uber failure, a few points below is a normal failure, and a tiny bit below is a sort of failure (ie you convince the guards not to kill you on site, but they will throw you in the dungeon).  And similarly for successes (sort of success, normal, and super awesome success)

We've decided to add a new optional rule that says when you get exactly the Difficulty level, it counts as a barely success.  A few examples: John's character is trying to jump from rooftop to rooftop, John's roll plus his strength plus athletics is a 12, which is what the DL is.  The GM could say, "You make it to the other roof, but only barely, and you're hanging on by your fingertips."

Another example is if you're trying to pick a lock and you roll exactly the DL; it takes the character longer to pick the lock and therefore has a higher chance of getting caught.  Or, you pick the lock, but your pick breaks in the lock, leaving you without your pick and unable to relock the door.