Here's my basic thought process about enforcement of our commercial rules:
Self-promotion with multiple links = no (especially if it's multiple links in one thread, hit-and-run linking and/or raising several old threads)
linking to the allowed self-promotional post in the commercial section = okay as long as it's relevant to the current
discussion and used sparingly
linking to products and sites (not self-promotion) relevant to the current
discussion = okay
Obviously these are generalities. We tried to set up the rules with the integrity of our site in mind, but we don't want to be so rigid as to make the site difficult to use or to be lacking in discussion and resources within threads.
I don't anticipate that any of our long-time/regular members would overstep when contributing to the discussions here.