With digital files there are no limits on retouching. My goal in using Photoshop is to make the space look real. I think that over-corrected images have a tendency to look manipulated. The small imperfections are what make the images look more credible. I see a lot of over-retouched images using automated systems within Photoshop or Photomatix to process HDR images. Unfortunately they look very fake as such systems, without human control, apply a uniform set of rules with no reference to context or goal. A photographer continues to need to be the one deciding where an image needs enhanced detail, not automated software. I do not ignore such automation, but I use it to preview, rather than produce. I layer many images shot at different exposures, then I use Photomatix, for example, to get a glimpse of what can be done with the set of images, but I then manually select each area that I want enhanced and those that should remain as they are. I want complete control over my shadow and highlight details in all my photographs.