I think a lot of people have used categories and tags just because there are there…IMHO they should be looked at as organizational tools vs. URL/SEO tool.
Wisdom Alert!!
I’ve yet to figure out the value in “tags” but categories, sections, weblogs, channels, et al, are nothing more than organizational tools. EE makes ‘em easy, so EE users can find complicated ways to use ‘em.
...I would still take more templates with less less conditions…
That tends to be my method as well, though, to be fair, work flow, experience, user ability, future users, etc., all fall into play here.
Bottom line for me is build URLs for people not spiders or provide good navigation so that URLs really don’t have to be that memorable and clean…
EE’s basic method of template_group/template/entry_name is about all that’s really necessary for good SEO (which, mentioned earlier, is far more dependent on relevant content and links to the content than keyword/tag density which reaches a point of diminishing returns very quickly).
Adding a category_name to the URL string does little, if anything at all, for SEO. In fact, it could be argued that even building URLs for people is an effort in diminishing returns. Who types in whole URLs, friendly or complex, anymore? It’s more likely that any URL to an entry or a category or a static page or another site is linked and clicked to 99.99% of the time.
This may look prettier—http://mysite.com/killroywashere— but has no advantage in SEO or user friendliness over this—http://mysite.com/index.php/news/local/killroy_was_here_tag_tag_tag.