The legal system must above all be predictable, and you'll have a very hard time being predictable if your legal rules are written like "citizens should do X unless they have good reasons to do otherwise". At the very least, those good reasons to do otherwise should be elicited explicitly (but they can, and do, change over time).
Take speed limits, for example. Probably we can all agree that driving at 100 mph in city centre is a terrible idea, so the law forbids it in basically every nation (elicited exception: you're a police officer during an high speed chase). But the actual speed limits probably won't let you drive at 100 mph anywhere, not even if you are the only driver along a giant straight road in Nebraska with perfect weather. If you still respect the official speed limits in these conditions, probably is because you don't want to get a ticket from the police (or because you don't trust too much your own driving abilities, but let's just ignore this case for now). Legal positivism applied to speed limits is John Nestor, and I would guess that even the large majority of legal officers don't drive like Nestor, or he wouldn't have one-third of his Wikipedia entry dedicated to this. Even in this case, I think that letting an occasional Nestor cause traffic jam is still a better idea than just writing down "drive at whatever speed you judge appropriate".
On a more general level, I think that a simple fear to get punishment from the upper level of the bureaucracy should be enough to justify the simplest form of legal positivism. Stick to the letter of the law, and no one could formally accuse you of any infraction.
The proper venue for deliberation is the law maker ie parliament and such. If a law is bad in can be struck down rather than made impotent or circumvented. If rule appliers disregarded the deliberation and results of parliamanets arguing the law and supreme courts making fine distinctions would be in vain.
Law isn't neccearily what is good or how things shoud be done but what there is permission for and how things are organised. There is a difference between appeal to authority and "by the powers invedsted in me". If I am order to pick an apple formyself from a neighbours tree and I instead reason that it is more better or "rational" for me to pick a lemon instead, even if I am right in that (say I have a apple allergy) I would be outside of the scope of permission to do so. Law could be construed as "socical will solifidied" where individual will overriding would place themselfs above the whole group.
If you make contrast or promises that a wonky yes your action options are severly limited. That's kind of the point. And yes you can't deduce promises from abstract principles and find some subset of promises that "everybody should follow". Rather for promises when they are given is a tractable historical fact.
If I understand right, your first point is that it makes sense for officials to follow the law because parliament and the courts are better placed to alter it. Another point is then that it makes sense to limit your activity for the benefit of the group ('individual placing themselves above the group')
These are fairly sensible reasons to obey the law. Does that mean law loses its force when parliament and courts are sufficiently incompetent or crooked? Likewise when acting for a small minority rather than the group?
Not sure officials think of law this way. Further, an open question whether a system could function with this kind of clause being widely accepted by lawyers and legal officials.
In a democrasy one could always run to be a representative and hopefully one has already elected in representatives that respond to the voice of reason. However if one loses such elections or other representatives don't respond to your pleas then it is a question whether one should "lose in peace".
The officials need not be that aware of what all it took and how high quality the specifications are. They don't need what kind of poltical compromises or technicality generalizations have gone into them. But a property of following a law because it is the law is that if a new improved law gets passed then that will be implemented in full force.
Evil goverments or nations are a possibilty but if one is to rebel then it is likely to be towards the whole system. If you pick and choose what you follow then what the official word on that is of no consequence. Theoretically it could be possible that a situation so heinous happens that it would be unethical to fail to rebel. But a single persons perspective is so limited that a "duty to rebel" is unlikely to be relevant often as many acts that seem locally very backwards could on the whole be defensible. Note for example if you break a law that has been passed as a political compromise for some other right to be recognised one jeopardises that right being recognised. And this even if the broken law is truly unjust. Is it justifiable to prevent an unjust killing if it leads to full blown war?
And the proper time to resist a bad law is when it passes and it should sound alarm even before it gets applied. And in fact when it is being debated whether its bill should pass that is the most critical time to act (vote those evil laws down).
The possibility that someone could be sleepnig on the wheel is not a reason to disconnect the wheel from the tiers but rather grab a better hold of the wheel.
And, if so, is this a bad thing?
This is a short essay on modern law; specifically, how it is possibly irrational, and how this irrationality could in fact be necessary for large legal systems to operate. I conclude with some observations on potential wider significance of this phenomenon.
Modern Legal Reasoning
It is fairly well known that you cannot reason your way around breaching a contract's terms. Regardless of what is rational or commonsensical, you will be forced to pay on the basis 'the law is the law.' This literal-mindedness is known in legal circles as 'Legal Positivism.'
Legal positivism is essentially the view that 'the law' (the set of rules considered legally valid in a jurisdiction) is determined ultimately by social facts. Thus, when we want to work out the law, we look at historical processes, such as legislation going through the correct procedure, or judgements being issued from recognised tribunals. When you ask the small claims court 'why is the law the law' they can respond 'it says so according to the Invoices Act 1998, which was passed by Parliament.'
If the official takes the law as a non-defeasible reason for action independent from its practical or moral reasonableness, this can lead to irrational results. This is a symptom of law's reliance on arguments from authority: 'But why? Because X said so.'
Rationalist Counterargument
Such rigid thinking is distasteful, and is met with the riposte 'just because something is the law doesn't mean you ought to follow it.'
The rational account of rule-following has a different approach. It goes something along the lines of: "in general, it is best to defer to legal rules, all things being equal, but should a legal rule prove demonstrably net pointless or harmful then it should be ignored."
Thus, behaviour should be oriented according to the law only if it 'makes sense', taking into a wide range of factors, such as:
Empirical Digression
This appears to be a reasonable way of approaching the law: do courts, lawyers, and most officials, actually treat law like this?
We do not know. At most, we know the law is applied consistently in modern legal systems with little discretion or rebellion by individuals judges, officials, or lawyers. This is what is called the 'massive agreement' point: the law is stable enough that big groups agree on it.
The challenge is then explaining this phenomena. The optimistic view holds that this is a 'massive consensus': all the judges agree on the current law because, all things considered, it is the best compromise between stability, justice, and, perhaps, for some of the other factors mentioned above. The cynical view holds there is 'agreement' for the same reason the military has 'agreement' on discipline, organisation, chains of command etc: there are conventions which the majority follow somewhat unthinkingly.
The second view is the legal positivist view, discussed above.
Let us assume provisionally this is in fact the dominant few at least in the context of commercial law: legions of petty officials applying the law like rubber-stampers. From personal experience with the law and lawyers, this is not implausible. It is frequently impossible to argue your way around an official determined to 'stick to the law.'
What does this suggest about the practical uses of blind obedience to the law?
The Value of Not Thinking
One is that the legal system actually relies on officials taking an unquestioning mindset.
Modern legal systems require consistency, and therefore predictability, to meet the needs of modern society. When similar facts come before the courts, similar outcomes must come out across the jurisdiction, over a steady period, and over thousands of repetitions. [1]
This is a challenge for a system built using people, given people have a tendency to diverge from one another and develop their own ideas. How to prevent this? One solution could be a system of thought which discourages active deliberation and free thinking. Instead of legal officials carrying out a rational calculus, they defer to authority. This prevents individuals interrogating the point of the rules they follow and possibly reaching different conclusion. Only with this structure, one which is arguably also present in the military and church, can homogeneity be maintained.
Think of this legal positivist mindset as anti-rationality memetic antibodies. To say 'that's not the law because it's irrational' or 'who cares if it's the law, it's irrational' is anathema to the legal positivist as it contradicts their belief law is valid based on its source alone. By resisting it, however, they ensure the continued smooth operation of the legal system.
Summary
[1] Note, this is not the case across the legal system. Some areas of law require more certainty than others. High certainty areas are Property Law, Contract Law, Commercial Law, some areas of Criminal Law (Traffic law) and Tax Law.