Disqualified for too much PP?

I think it's safe to assume that "minor PP" refers to such use of post-processing tools as contrast, sharpening, cropping and light balance, all with moderation and sparingly. It should show the resulting image as being not post-processed, where nothing stands out as an obvious effect. Even HDR should be done in this manner, since exaggerration is usually the main reason for "No HDR" rules.

Contrary to that, composites, cloning and similar changes in the overall image contents are not "minor PP", and should be regarded as more compex operations aiming to change the picture story. Sometimes the hosts will allow "removal of lesser distractions", so removing details from the image will be okay.

But in general, minor post-processing interventions should be invisible. In that sense, even the minor PP will maybe not acceptable if any of the tools used leave telltale residuals. The most important characteristis of every good post-processing is that it is not noticeable.

Of course, there may be challenges where heavy PP is a requirement... that's a specialty.

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Fil