From the WFRP Companion pages 61-67.
I kind of like these rules, and may be trying to adapt them for DH use. Essentially it allows a skilled character who fails a roll to fall back on a secondary skill test to improve that failure to a standard success, or to increase a standard (or other) success by +1 degree.
The balancing fact in WFRP is that these rules require Fortune Points (aka Fate Points) to be spent in order to use them. I dont really like that aspect of the rules as it makes no real sense to me other then as a meta-rule game balance device. Im going to be reading over these rules and what not while on my plane flight today to see if anything else clicks in my mind.