I think there will be ambiguity and good faith discussions and clarifications to settle expectations. I also think that people who insist on it will always be able to split hairs and invent arguments.

If the company has a policy that says "No unwanted touching of coworkers" and one employee hovers his hand over coworkers while taunting "I'm not touching you" the problem is not with the guideline. Likewise, if you say "No politics at work" and someone keeps coming up with creative arguments of the form "Technically isn't this politics" then the problem isn't with the guideline either.