I agree with you definitions and reasoning, I disagree that prudence and decorum don't serve in some circles.
Prudence and decorum just change to fit the context of the circle. For those who have little to lose but their own life, prudence may take the form of kindness and charity. Decorum is just upholding a tradition within a circle, and traditions form at every level of society to keep what works moving forward.
I would argue that prudence and decorum are good tools to have no matter what circle you move in, you just have to adapt the tools for the job :/