having keywords from the post title in the url also can help search engines judge the quality of a page

including the keyword in the url just gives another chance for that keyword to match the user’s query in some way. That’s the way I’d put it.

Matt's comments must be taken in context, keeping in mind the extensive guidelines provided by Google as a warning that keyword abusers and unethical practices will lead to banning.

Nevertheless, keywords are a legitimate tool in structuring information. Communicating clearly requires you use a consistent vocabulary, in an attempt to avoid confusion and improving style. At Enclick we are careful with keyword selection and keyword usage on web pages. A keyword analysis identifies the list of keywords that are most relevant and important to a client's site. The keyword list is taken into account in the web page copy and URLs. Keyword density measurement tools are used to keep track of whether the web page is staying relevant to the right keywords.

The use of keywords is not about gaming Google, but about communicating clearly both with users and software programs like search engines.