I cannot disagree with anything you wrote, Nathan. That is, in fact, pretty much a perfect summary of my views on photographic provenance.
It may be worth noting as well that my personal definition of a "photograph" is not the final silver print, or inkjet print, or negative scan, or monitor display, or even one's retrospective coffee table book. Those are all reproductions . It's the negative itself. And only the negative itself. The thing that originally, and spontaneously without any assistance from the photographer, received, registered and preserved the pattern of light that originally reflected from the subject.
That original negative (or positive, in positive-only processes such a transparencies, instant film, and daguerreotypes) is therefore the singular first generation object of indirection. Before it there are no photographs, only the original subject. And after it there are only reproductions. It is the one-off, unique evidence that the scene which spontaneously rendered itself upon it truly once existed directly in front of it.
In an example that 'blanksy' and I have toiled over several times, the reason that Alexander Gardner's glass plate negatives of the Hanging of the Lincoln Conspirators are so breathtaking is not that they tell us those four souls died at the end of four ropes. We already knew that from the history books before ever visiting the Library of Congess, donning white cotton gloves, and being handed the actual glass plates to hold up to the light and gaze at.
No, the reason they are breathtaking is that while looking at them we suddenly come to realize that those fragile plates in our hands were, at the moment those four souls finally hung, physically present inside of Mr. Gardner's wet-plate camera, situated on the second floor of that building overlooking the gallows, only about twenty yards from the doomed prisoners, on that long ago March afternoon. And now we are holding those exact same glass plates in our hands 148 years later thus affirming, via these singular first generation objects, that those events did, in fact, really take place.
It's that epiphany that creates the stunning credibility that takes our breath away.
The negative bears silent witness to the reality of the original events rendered upon it. That's what photographic provenance means to me, and why it is so crucially important to me that a real photograph needs to possess it.