I only tried refusing to sign something once. Nobody ever called me on it. I got nastygrams via email. I ignored them. One day, they stopped coming.
I cannot guarantee that will work in all situations, of course. You basically are calling their bluff, and it could backfire. But if they really are bluffing, all is well.
I think the problem here is that of 'who's bluff are you calling'.
Usually the people bothering me about these types of things aren't the one's doing the bluffing about it...they are in their own loop of compliance and nastygrams. They are trained to be compliant and don't have a mental framing that this stuff could be a bluff. That makes me a lot less confident of how they will react or their willingness to be rational.
I cannot guarantee that will work in all situations, of course. You basically are calling their bluff, and it could backfire. But if they really are bluffing, all is well.