You may already be aware of this, but the below behaviour plugin developed by someone in the cakephp community can help out with more SE friendly URLs for websites.

http://bakery.cakephp.org/articles/view/slug-behavior

For me, I’m building a bespoke content management system using CakePHP, and this is pretty useful to specify a URL for my content. It does mean that your controller has to do the lookup based on the slug rather than the id though…which means if you’ve already built a system, it might take a fair bit of code re-work to introduce this behaviour.

Also, you’ve said that web developers can do little to improve SEO, which is kinda ok as a lot comes down to the content of the site, but I would emphasise that they probably have the most important job in that they must ensure that title tags and meta descriptions are 100% configurable. The capability of that in a system is pretty fundamental for SEO.

Also configurable URLs are pretty useful as well.

In writing SEO proposals I usually sort the work into three categories 1) on page factors, 2) off page factors, and 3) information architecture.

The first of these is largely the responsibility of the site owner - what content goes on each page, how is it arranged, etc. The second refers to backlinks that this post talks about which are often uncontrollable. The developer has a lot to say about the third - the website’s information architecture.

In addition to the points made in this post (title, URL’s keywords, control of meta tags), the developer has alot to say about items such as URL canonicalization, navigation elements (menus, sub-navigation blocks, breadcrumbs, etc.), and production of sitemaps. All of these can be important elements for search engine optimization.

In general, information architecture works best for SEO when it is obvious and systematic. Used properly, frameworks such as CakePHP are very good at being obvious and systematic.