Purist or realist?
When you 'dial in' an image you are making it look better on your display but no one knows what it will look like on other monitors or displays.
If I detect manipulation of an image (for example the obvious over saturation in the original post) then I discount all the images in that listing or sale. If someone is diddling around with post-processing of the images then I assume that they are also capable of smoothing creases, substituting over tears, or Lord-Knows-What other graphic illusions. A red warning flag for me.
Obviously trying to determine 'intention' is a totally slippery slope which no one should try to navigate. And just as obviously there is a difference between polishing a car before you sell it and pouring saw dust in a manual transmission to quiet it down.
But the lack of transparency in image manipulation...and just how 'main stream' and acceptable it has become is not good for our hobby in my opinion.
Most of the 'color threads' in this community reflect a lack of information not only on ambient lighting conditions but also image post-processing. How can anyone form an accurate opinion without having this information in a stamp color thread? Howe can a person make a confident buying decision if they know that at least some image manipulation has occurred?
I think that accepting that most images have been manipulated serves to perpetuate the abuse (especially for professional sellers, dealers and auction houses). <shrugs>