The fair Escape rule represents a character taking emergency action to avoid another character that they don’t want to get near to them, such as vaulting tables and leaping through windows.
You may (clearly) call ‘Fair Escape’ at any time before the character from whom you wish to flee gets within conversational distance; a few paces! If the character is within such distance you may not activate Fair Escape, and will have to do the challenges as normal.
Fair Escape may be used with disciplines, such as Celerity, Obfuscate, and Shadow of the Beast (Bat form), but only under the same circumstances. Such powers may be countered (i.e. you may call Fair Escape; Rapidity, but someone calling Fleetness will cancel out the Fair Escape). You may not call Fair Escape and turn into a Bat during a Brawl; such an action would have to be done as a challenge as you could be grappled.