Can anyone point me to a regulation published or a precedent established that gives guidance to the limits of the term "sufficiently representative".

This relates to the use of the term per s32.5.a of the Labour Relations Act, 1995 which is as follows:

5) Despite subsection (3)(b) and (c), the Minister may extend a collective agreement in terms of subsection (2) if –

a) the parties to the bargaining council are sufficiently representative within the registered scope of the bargaining council; and

b) the Minister is satisfied that failure to extend the agreement may undermine collective bargaining at sectoral level or in the public service as a whole.

Obviously the purpose is to allow some leeway below 50%+1, but just how much leeway could still be considered "sufficiently representative"?