The instructions for the exercise tell you straight up to ignore any and all exceptions, yet 30% of people chose to apply their own judgment in the police and ambulance case because it felt right to them. Very telling.
It should be comforting that people are able to use independent judgement when faced with a nonsensical situation, situations that illustrates a glaring lack of detail to the law or rule rather than anything else.
Basically the more terse a rule is, the more it requires the enforcer to use their own judgment.
That game would only be supportive of the point the author wants to make if the rule had a few paragraphs of examples and defined vehicle.
Instead the author hand waved away the case of a rule with examples by saying that nit picker could always find ambiguity. So instead they gave a overt terse rule that defies common sense. It’s a strawman attempt of a example.
Deciding that something violates the letter of the law is not an absurd conclusion. That's just step one, and the more important places to involve judgement come after that step.
It's telling that 70% would apply immoral guidance. "Just following orders."