Abuse of process is a new and relatively ill-defined doctrine, which indicates that it is a reflection of legal change in process. It has developed, and is developing, as a legal 'reason' for dealing with some underaddressed phenomenon of law. So trying to pinpoint it's essence is a bit of a mug's game, the easiest way to assess it right now is to just look for cases were judges have relied up it, and characterize those situations.
