I had a good lesson last night. Parry sixte, extend, and then step into it if your extension doesn't quite reach. You touch with the hand pronated, and after touching come back immediately to on guard. You can also, if you are in too close for an extension, drop your weapon hand and come up in a "dig" to surprise and dismay your opponent. A parry in prime can also be turned to your advantage, as can a high septime against a fleche. I am, of course, speaking of epee, where there are no rules of right-of-way. (My personal favorite is to close nearly corps-a-corps, binding the blades, and then strike home with your main gauche. This is frowned upon in competition because it uses up opponents pretty quick, and it can be pretty messy with all the blood. Of course, you keep your main gauche hidden unless you want to use it as a bladebreaker, but that's another technique.)