First, just on reproductions and "originals" - with photography, the negative is rarely ever the final intention for the work - a it's a step in the process (occasionally a transparency might be - but even then it's usually an enlargement).

The print is the final work, the negative is "just" a matrix to allow you to make that final work - and each print is an original based on that negative (and other things).

You can make a comparison with cast sculpture - the clay covered armature etc (what do they call those things) or the other parts of the process - wax "negative" and so on aren't the originals - it's the final bronzes (or resins or whatever you are working in)

"Most printers I know pride themselves on exact duplication from one print to the next, which conjures up unsharp masks and digital prints for example(please, lets not get into a digi debate here, these are philosophical concepts I'm struggling with!) Where does this attitude come from? I'm guessing that it is from the notion that a photograph is a reproduction of the physical and the observable. In order to be "true" to the scene, all prints have to be exactly like the first in the edition---very much like what we'd expect to find in a road map. If one map showed the Santa Monica Freeway in Las Vegas, another map in San Francisco and still another in Portland the value of such information would be worthless because it has no bearing on reality, and captured reality is something to strive for in say medical and aerial photographs, portraits, historic records, that sort of stuff, but what about the art for art's sake photos where there is no bearing on reality from the outset? Why is exactness in reproduction in that case so important?"

It isn't - photography isn't about "a reproduction of the physical and the observable" and certainly not about an exact reproduction - it's about seeing how something looks when you photograph it - which may be very very different from how it "actually" looks. All I am concerned about with my prints is getting them to show what it is I saw - and to repeat that clearly from print to print - and how it looks may have nothing to do with how the thing "actually" looks.

When we photograph something (in the sense you are talking about - personal, artistic, creative, call it what you will, as opposed to "record" shots) we aren't trying to re-create that somnething; rather, when we depict something, we are giving our account of how we saw that thing. If I photograph some still lifes of apples, I'm not actually concerned with apples per se, but with my perception apples. "I photograph something to see how it looks like photographed by me" as Gary Winogrand said - in some ways it's as simple as that.