If you decide to ignore certain laws that is your choice, however I don't see how recommending that you follow the laws invalidates the rest of the advice in a given guide.
I would regard any tip as a recommendation rather than a "must do" because more than likely there will be situations where following a given tip would not be the best choice.
I think of laws in the same way. Traffic laws are intended to keep things moving, to promote predictability, and to keep people safe. That doesn't mean following the letter of the law is always the right thing to do, but in general it is.