Several bad analogies. First off, your assault rifle analogy is bad. If the design calls for a 300m range that's the target. If it can perform up to 400m with slight or no modification well bully for you. The thing is that we aren't talking specific examples here. If you are given a project goal, you try to fulfill it. If you can then you can start cranking up what more you can do with the same system. But the basic idea is to get a system that can do xyz things. Secondly, British tanks fulfilled their design specs and while combat performance varied this was more due to British tactics rather than any critical shortcomings on the vehicles themselves. Major point here being the Brits like any country that built weapons in WWII went back to drawing board and improved on the last design they had. Weapons evolve to meet the existing / perceived threat and while people usually leave some room for future improvements, there's a limit how much you can predict the future and there's no point in chasing pipe dreams since the weapon you designed today might be obsolete tomorrow requiring you start all over regardless.
Engineers build to the specifications you give them, yes. But someone has to look at a situation and decide what they are likely to need, and then give those requirements to an engineer. If I need a 300m effective range, the smart thing to do is tell them to build me a 400m effective range. That's what happened with the british tanks, they would have done what they were built to do, but what they were built to do was not enough, as a result they were heavily armoured but slow and under gunned and largely ineffective against enemy armour. Had someone thought that they might actually need to fight enemy armour, like almost every other tank building nation had considered and planned for, they would have been much more effective weapons. An even better example is their fighters. The RAF operated pre war on the theory the 'the bomber will always get through' and concentrated on building bombers and turret fighters to the exclusion of almost everything else. They got lucky in that someone figured out they were wrong just in time to get Hurricanes and Spitfires rushed through a design process and into production and started replacing turret fighters before WW2 actually kicked off, if barely. You don't just build to counter what exists now, you have to try and anticipate and counter what the enemy is developing, it's easy to loose sight of that these days because most advanced weapons developing nations have not been enemies, but why do you think there was such a collective pants shitting when the Chinese stealth fighter was displayed? It was because no one knows if it will be roughly equal to the F-22, but if it is, then it will be the first time since shortly after WW2 that the west does not have a comprehensive technology advantage largely because they failed to anticipate and attempt to counter opposing developments. It's foolish to expect to be able to predict what you need to counter though, so you are better off being more capable than strictly necessary in a broad spectrum than being light years more advance in where you think you need to be.
Third a tank can be a credible threat to a fighter without needing to fly, in fact it can be a far more credible threat to a fighter than a single soldier will ever be. This is simply due to tanks ability to carry around bigger weapons and sensory arrays. But only if we design the tank to do this in the first place. A simple soldier can be a counter to a tank but only if he comes equipped to do it, but he cannot carry enough shit on him to be as a great threat to a fighter as a tank can. Even supers soldiers are limited in capability by the equipment they receive and while they might be more adaptable than regular infantry their overall performance is reliant on the kind of gear they receive. As a premise it's silly to assume that someone would make super soldier that exceeds the set parameters for it, or that this could even be done.
A tank alone will never be a threat, it needs a crew to think for it and drive it. A man always has the potential to be a threat because he can think and act independently, can look for weapons and arm himself for the task at hand. The more capable he is the easier this is to achieve. That is the biggest advantage to an individual as opposed to any piece of equipment, they can be re purposed by giving them different stuff and a few instructions. Sure, they won't be as effective as a specially trained operator, but will be more effective than the tank with an anti armour cannon trying to engage large numbers of infantry single handedly.
Again says you. There's no universal rule that says a super soldier no matter how long it takes to make them has to be a long term investment. If you are building soldiers you can assume there's a valid reason for doing so but that's about it.
No, if your creation time exceeds your life cycle by a margin that significant then your production has to grow exponentially just to replace casualties. There is no way that it is sustainable.
I never said I'd make him extraordinarily strong. Point I was making there's no harm in him being strong if I can do it without making him excessively large. Physical strength is all fine and dandy in several things that come to tanks, but I wouldn't make him into a hulk either. Like I said, if I was making an all rounder super soldier, he would be about how I described him. If I was making an infantry super soldier, I would modify him according to the probable threat he would face.
The point is you can't. Physical strength is proportionate to muscle mass, that is the way physiology works. All men of average height, mass and build will have roughly the same strength and one of those, likely all of them, have to increase to make him stronger.
And I was merely illustrating you have no idea what you're talking about when it comes to trucks and APCs i.e you were wrong. You do realize what you just said applies to all things? Trade offs have to be made all the time and a dedicated system beats a general purpose one in the area it was designed for.
Do you agree that you can't make an unarmoured truck and an APC with the same carrying capacity, size, weight and speed? Because that was the only point I was trying to make.
Basically yes. But this is again dependent on how and why we are making our super soldiers. A 210cm hulk will not make a good tanker simply due to his size if the vehicles are designed to smaller people, nor will he make a great fighter pilot for the same reason no matter how good his aptitude for either was otherwise. Vice versa, an average sized guy has the potential to make an ok infantry man and far more easily fits inside vehicles.
Granted, but if your vehicle losses are that much lower than your crewman losses that you have to replace crewmembers with specialised infantry, you have more problems than supersoldiers are going to fix anyway.
But it underscores the whole point of 'it depends on what you want in a super soldier' and what your technology base is capable of. Its tremendously open ended, and can be approached in different ways, but you seem to adhere to some bizarre, nebulous and hard to grasp (for me at least) standard that you feel exists that requires certain traits.
Well without bizarre pseudo magic powers like throwing lighting from their fingertips or chameleon into their surroundings, largely the factors that military training already tries to increase in people. Stronger, faster, able to detect the enemy from further away, no chance of panic, disciplined and unshakably loyal, willing to die if ordered too. A soldier, simply better at it than an unmodified person can be.
Again unless you're going to invoke magic here there's limits to what you can engineer your super soldiers to do without giving them fancy high tech equipment (which is independent of super-soldiering), and even then engineering those abilities are going to involve tradeoffs (you will have to make them bigger to fit everything in, which is a drawback for a number of reasons - and even then you may have to make sacrifices and compromises WRT perfomrance to engineer it all in. You can't have everything.)
What you seem to be thinking of is commando-Jedi types or maybe something like Spectres from Mass Effect, which basically have funky psychic or magic powers to augment their 'normal' human abilities.
No, I haven't even thought about any magic or force powers or anything similar.
You seem to be operating with this certain idea that 'super soldier' is somehow a well defined concept, or that the definition in question is a well defined or practical one to begin with. As I said there re no absolutes here, its all relative - some 'approaches' to super soldiers will be relatively more sensible than others, but they will still require and have tradeoffs that will hamper them in other ways, unless you throw it all to the board and embrace magic (which is basically what Space Marines do.) If we want efficiency we'd be going with robots for tasks.
A better example (not totally, but better than Space Marines) of a less insane 'super soldier' are the various kinds of assassins, in which rthey re super powered but they specialize. You have Callidus and Vindicaire, and Eversor, etc..
Thing with the assasins though, is that two of them require a very limited substance to create that space marines don't (blank humans and the shapeshifting drug respectively) and if all the resources you threw into making the sniper and close combat assassins were used to make space marines with a focus on those particular skills, you would get a larger number of very good sniper space marines, very good berserker space marines and probably a healthy number of ordinary space marines left over. Now, the sniper marine wouldn't be as good a sniper as the current assassins, but would be better in almost all other aspects of combat, and the berserker marine would not be as good as the berserker assassin, but would still be an excellent ranged combatant if he needed to be. And that seems a much better way of going about things to me than the way it is done in universe.
If you're going to be talking about supersoldiers anything you have to be giving up on the idea of absolutes. No supersolider is going to be 'perfectly' efficient or effective compared to alternaties, nor is it goint to be perfectly (or even mostly) versatile - tradeoffs demand it unless you break any pretense of plausibility (think about it this way. would it seem reaosnable if you decided you could create a magic potion that turns every soldier into a superman? you can certainly do that, and it can be made to work, but its pretty far down on the plausibility scale. This is getting precisely into the sorts of things Mike was talking about, in fact.)
No, you will never get that perfect efficiency, and if you try for it you run into problems. Ultimately you want your supersoldiers to be able to shoot, but if they run into something that can outshoot them they can beat it in a knife fight, and if they can be beaten in a knife fight by something they can outshoot it. They are going to be an ace in the hole anyway, so you don't want to have an ace in the hole that can be made useless by something the enemy does, they need to have the versatility to have a chance against almost anything the enemy can throw at them.
I think you're using a poor analogy. You're not talking about 'redundancy', you're talking about diversifying. This is like saying you want to build a truck to carry heavy loads, then deciding you need to fit waterskis and a boat engine on (or propellers and wings) onto it because it might need the versatility. Like the transforming vehicles in starcraft or something.
No, I'm saying that if you are building a number of trucks designed to go off-road and a number of trucks with water skis and a boat engine that can't go off-road, you would be better off running two production lines both producing trucks that can go off-road and have water skis and a boat engine, that way you will get more versatile trucks and long term will likely have more of them.