Lurker,
Welcome back.
I'm not sure you are grasping this finicky legal stuff, any more than Fume is grasping the fact that Wicked Willie has the full backing of the money men:
"Because individual employment contracts are legally enforceable, many collective agreements are indirectly underpinned by law."
I feel the need to point out that there could be a vast legal difference between "many" and "all". It is only an interpretation on my part.
But as has been pointed out, the legal teams will know how to argue this one.
Cheers,
D