Daguerreotypes were never anything but flipped/flopped. If I'm presenting a history topic to students and there is an image that has been "corrected" I will un-correct it so it can be seen the way it was even if there is text. Makes the point.
I reverse negatives in two situations.
The first thing a portrait client sees is a reversed proof. It is the face they see in the bathroom mirror. I sometimes get a response like "You're the only photographer who has ever got me the way I am. All the others seem to get me wrong somehow." The other portraits in the shoot are the right way round so that everyone else will recognise my subject properly.
The other flip involves self portraits when I wear a particular T-shirt on which the words "GUARANTEED NO DIGITAL" are stenciled backwards. By flipping the negative the positive shows street signage reversed, cars on the wrong side of the road, shirts buttons wrong, wrist watches on the right, and so on. In effect I create a Bizarro world in which everything is awry except the message on the T-shirt!
Sure, check out my webpage home page....it's upside down....but looks way cooler that way.
I sometimes print from a reversed negative but rarely when it's a picture of a person - it doesn't seem right somehow. But that's just me, and I don't care either way if other people do it.
I actually was doing a styilized and abstract multiple generation lith negative sandwich print onto photo paper as a kind of an 'electronic flower' effort.
The last print I exposed under the contact frame I must have flipped as I put it into the tray, becuase as the image came up in the developer, it was upside down.
The abstract image now looked like some kind of space ship, and the part intended as the stem for the flower looked like a smoke trail. I really liked it, even better than the post modern age flower image I had started to assemble.
I mounted it, as the space ship orientation, and submitted it in a large print competition, and it came back with a special award ribbon - serendipity eh!
Since emulsion-up is normal when you make dupes, the "flop" thing could get really confusing if you weren't very careful. I think I must have seen the word "flop" several thousand times.
"Flop" in a photojournalistic context:
The orientation of the image, right reading or mirrored, may or may not be important to the story. If it isn't, art direction will frequently take the liberty to flop an image if graphic considerations require. Why not? It's done all the time.
In one instance in my experience, an image of a train pulling into the station at night was flopped to keep the train from driving off the page. Nobody ever noticed, because the illuminated numbers on the locomotive were halated beyond recognition. It could have been heading north, or it could have been heading south. Maybe someone intimately familiar with the Yakima, WA depot, after studying it microscopically, could have found some clue that would reveal a possibility of "deception" but who'd waste time on that? The value of the image to the story would remain intact, regardless, while the presentation of the image in the layout as taken would have sent the reader hurrying on to the next page, missing the story entirely.
No, never, at least not on purpose. My images are literal representations of the landscape that they represent.