More to the point, you fight the good fight within the framework of what is provided to you - what you don't do is pull shenanigans and then have to defend those shenanigans.
Managements biggest fear (in Operations anyway), without any hesitation in my mind, is that the Union actually unites and stands together - if the company agrees to a contract that is legally binding, and then the Union uses that contract, there is no way out.
If you don't use that contract for whatever reason, then I have limited sympathy for you.