A collective agreement shall be conclusively presumed not to have been intended by the parties to be a legally enforceable contract unless the agreement—
A collective agreement which does satisfy those conditions shall be conclusively presumed to have been intended by the parties to be a legally enforceable contract.
If a collective agreement is in writing and contains a provision which (however expressed) states that the parties intend that one or more parts of the agreement specified in that provision, but not the whole of the agreement, shall be a legally enforceable contract, then—
A part of a collective agreement which by virtue of subsection (3)(b) is not a legally enforceable contract may be referred to for the purpose of interpreting a party of the agreement which is such a contract.