The para (4) bit in Schedule 8 is left over from the good old days before JAR when one needed a type rating for every aircraft one was going to fly for hire or reward. If, for example one held type ratings on the PA28 and PA34 one could instruct and test on those types wherever and whenever one liked. The instructor rating, on the other hand, would, for example, be endorsed for 'Group A and B' and one could instruct on any aircraft in those groups, for which one didn't hold a type rating, only within the 'flying club' restriction.
Since the advent of JAR and Class Ratings, the 'flying club' restriction is no longer relevant to FIs who hold professional licences, who can instruct within or without a flying club on any aeroplane for which they hold the relevant class (or type) rating.