The painting on the top of the Sistine chapel is beautiful. Moral is not murdering your neighbor because you don't like the way he looks. Sure, you could come up with arguments against them, but those arguments are going to be pretty strained and you won't find many to agree with them.
Clear and unmistakable means that most reasonable people will agree that something is so. Granted there is some ambiguity in most and reasonable. But that's not as uncertain as say, "Is this post-modern art beautiful?", or "Is going 5 miles over the speed limit moral?"
Fundamentally, you can't get 100% agreement on anything. There are people who argue the earth is flat. There are even arguments that everything about you is entirely contained in yourself and that any perception, sensory or otherwise, is fundamentally subjective and that knowing anything outside yourself is impossible. Making the whole world black/white without any grey doesn't really work.
The basic ideas are you have a medical assessment before you deployed. That did not find the problem. During the deployment, you develop symptoms. The normal logic would follow that the disease that describes the symptoms would therefore be new. They need to come up with something solid, not mere conjecture, to refute that. It's not that, well, we can't prove the fibro started during the deployment, maybe it has been a process building for a long time. Fibro is further complicated because the VA says fibro is just a likely development from a deployment. Correlation is not causation, but the statistics are weird enough that they feel any former deployment service member who develops fibro, it is probably related to their service. If the VA says its there, how can the Army then argue they have clear and unmistakable evidence?
Now it is pretty obvious fibro doesn't just turn on over night. This same logic won't work for fibro over a weekend drill (or epilepsy). A weekend drill, the clear and unmistakable evidence should be easy to understand, by looking at the way these disease processes work over, well, every known instance.
Maybe they don't formalize the decision process every time, because well, in some cases it is pretty clear and unmistakable. Our basic instincts say people don't develop epilepsy over a weekend. If you wanted to say that yes, you did indeed develop epilepsy that way, it is up to the Army to provide the reasoning that says, nope, no head injury, no flashing lights, there is no medically explainable way for that to occur. They have the experts that would understand that a head injury or flashing lights is important, heck you might be all sorts of screwed up and can't write you name anymore, let alone not have the right medical knowledge. It can't be up to you to first say btw, I need my epilepsy covered because I had a head injury 2 hours before the seizure and the face plant, aren't those likely to be related.
I think I get your problem with it. It is sounding like every problem should be covered. That obviously isn't the case, so something is off. It isn't that the Soldier is always right and the government has to prove him wrong. It is more about, I think, they're supposed to be on your side. We take care of our wounded, not try to find way to screw them if they can't figure out the right argument. That is moral.
