... I see you talk about keyword / keyphrase density ... as opposed to optimizing your site for the surfer and not the spider ...
... I'm tricking the search engines into thinking I have a static site ...
There's meeting keyphrase density and there is keyword stuffing, those are two different things altogether. Provided that the content is visitor friendly and doesn't appear too repetitive, meeting keyphrase ratios is a basic part of Ethical SEO.
Appearing to be a static web page when in fact it is a dynamic web page can be ethical, provided that the content are the same.
I reworked my blog to suit your question
Ethical Search Engine Optimization
1. Does not include hiring oppressed people to write content
2. Does not recreate someone else's material and call it their own
3. Does not artificially make a web site appear important by manipulating it's link popularity
4. Does not intentionally hide content from the visitor that the search engines can find
5. Does not create pages that have little to do with the web site or are extremely similar to other pages within the web site for the purpose of giving the web site additional depth
6. Does not engage in cloaking
7. Does not manipulate redirects of any kind for an SEO advantage particularly for pages that no longer exist
8. Does not cooperate with link building management entities, buy links from link brokers or engage in link farming
9. Does not create a web page that appears to be about one thing but has content inserted within that is unrelated and intended for the search engine to find and rank