I need your collective wisdom. I am tossing around an idea of using Fate dice (actually, some custom dice of my own design that have + and - symbols) to add an "and/but" element to d20 games such as D&D & Pathfinder. The idea is to roll 2 or 3 Fate dice along with your d20. If you get double + or double -, they add a side effect. For example, if your d20 roll fails but the Fate dice read ++, your result is "failure, but something good happens". If your d20 roll is a success but your Fate dice come up --, the end result would be "success, but something bad happens". You could also get "success, and something else good happens" or "failure, and something else bad happens". For example, let's say your rogue is picking a lock. The roll succeeds, but the Fate dice read --. Perhaps the rogue's lockpicks break or get stuck in the lock. Or maybe the act alerts a sleeping guard. You get the drift. The problem I'm running up against is that the chance of a side effect - beneficial or detrimental - is the same regardless of your skill. An unskilled PC is just as likely to enjoy a beneficial side effect as a skilled PC. Any solutions OTHER than "use another system" or "I don't like it" are appreciated.