A character's effective skill is their skill level taking into account all the modifiers which apply at the time. Sometimes this will be the same as their basic skill level. Hand-to-hand combat skills are probably the most common example of this. He declares that he is about to do a feint in the next round of combat, then follow it up with a targeted strike to his opponent's weapon hand. In the turn where Lancelot feints, he does well enough to win his Quick Contest of Skill against Gorlois' Block skill by two points, giving him a +2 to count against his attack next turn.