In relation to the meaning issue, if the meaning of the

I am responding to a pm from danzig

I like the gist of what carcass said, and I will just add --- I don't believe that there are any SC questions in the OG12 or OG13 that come down only to a split based on discerning the author's meaning. In the few questions in which only a couple words are underlined, it's usually something very clear about, say, verb tense or subject-verb agreement. In the many questions in which a substantial section is underlined, there are often several different splits dividing the answer choices in different ways. Yes, the rules you cite (follow unambiguous meanings, and discern the meaning of an ambiguous prompt) are valid, but usually the ambiguity or incorrectness arises from a much more subtle split --- for example, an adverb/adjective split. Consider this sentence .....
Prompt: Frank was a bigger man than Sam, and he drove a corresponding larger car.
This is one of the GMAT's favorites --- they love the adverb/adjective split, and they particularly love doing this split with a tricky word like "corresponding" ----- here, we have the adjective "corresponding", which modifies "car", so the car corresponds to what???? That makes no sense. We know what the author is saying, but technically, phrasing it this way is illogical. What the author wants to say is: Frank is bigger, so he has a bigger car. Instead of the adjective "corresponding", modifying the noun "car", we need the adverb "correspondingly", modifying the word "bigger" ----- the relation between the two men (one "bigger" than the other) corresponds to the relationship between the cars (one "bigger" than the other) --- that's why we need the adverb modifying "bigger."
They also love this illogical structure with comparisons:
Prompt: Unlike the symphonies of Mozart and Haydn, Beethoven used a larger orchestra for his symphonies, and even a chorus for his Ninth.
Again, in colloquial English, this would probably pass as correct. We know what the person is trying to say. But, technically, it is illogical, because we are comparing pieces of music ("symphonies") to a person ("Beethoven"). We would have to reword the sentence to compare music to music or people to people.
Often when the meaning is unclear in the prompt, it's not blatantly unclear or blatantly illogical, as in the example with the courts and "should" --- rather, it's often a grammatical mistake that would pass as acceptable in colloquial English -- everyone would know what the person is trying to say, but technically, saying it that way is illogical or ungrammatical, and the GMAT requires that we re-word for logical & grammatical precision. In other words, the logical exercises you were recommending (would a court impose moral obligations?) are never necessary. We don't have to do that kind of reasoning. For the most part, we will know exactly what the person is trying to say, and we just have to find the logical and grammatically correct way to say that.

Does all this make sense?

Mike