1. In the method of matching a set of subject identification points against a set of reference identification points involving a matcher mechanism that employs a difference table, the improvement comprising the steps of: optically scanning the surface of an object that is deemed to be a subject input to provide said set of subject identification points substantially unique to the object being scanned, for each line entry on the difference table as a lead entry, providing a group of difference table line entries, limiting each group so provided to no more than one line entry for each of said reference identification points, for each of said groups, providing a quality value determined by a weighted relationship between the relative displacements of the various line entries in the group, selecting the most significant group quality value, and verifying a match between the set of subject points and the set of reference points as a function of the relative magnitude of the most significant quality value as compared to the number of identification points in a first one of said sets.