I don't understand why post-processing is considered a bad thing, even prohibited. I post-process all my images, and the least I do is to resize and sharpen them.
Consider this... most digital cameras save their images as jpegs. This involves -- besides compressing them -- a whitepoint adjustment and sharpening algorithm. Saturation and level adjustments within the camera are not unusual.
So, for example, I set my camera to "low sharpening" rather than the default "normal sharpening", because I believe that USM applied in post-processing does a gentler job than the USM algorithm that is built into the camera. So isn't that kinda ambiguous... since I do sharpening in postprocessing, my pics will not qualify, but if I set the cam to "high sharpening" they will, even though they will perhaps look oversharpened.
With all advances in optics and electronics, the human eye is still much more capable than any lens. Cameras just record reality, while the human eye adapts to the specific situation. Sensible color correction can bring an image closer to what the eye of the photographer saw in that moment.
I understand that retouching (the elimination of parts of the original image or addition of elements that were not) or special effects like certain filters are frowned upon, even local enhancements... but wouldn't in the end the viewer notice if something looked unreal?