In private non-union workplaces, the rules would be changed. Work to rule works only when regulations are unchanging and hard to change. To give an alternative examples, you have to jump to government employment,
"Under nationalization, French railroad strikes were forbidden. Nonetheless, railroad workers found other ways of expressing their grievances."
Because government as an employer is required to operate with some degree of due process, usually with some kind of civil service protection for workers, it de facto imposes the equivalent of a collective bargaining agreement on workers.
Private employees in non-union situations lack those protections. If they "work to rule", they get fired. If the supervisor recognizes that they are trying to frustrate the production goals, the employee can't claim he or she "was following the rules." Who cares?
One thing that always strikes me is how much the protections of union workplaces dominate the image of work, even for people who should know better. Working in a non-union workplace in the United States means "at will" employment, which means your boss can fire you because he doesn't like your choice of shoes that morning or for no reason at all. There are no "subversive" forms of public resistance. You resist in any way, you can be fired.
The only protection for defiance is collective defiance and the willingness to strike when fellow workers are fired. And that takes organizing and outside support to be successful in almost all cases.
Nathan Newman