SEO Long Tail - Can it Help Other Pages?

Long Tail SEO has been talked about for a long time as a way to increase site traffic. I want to postulate that it also helps other pages in your site do better.

Long Tail is a reference to a statistical relationship called a "Power Law" and was mentioned by Chris Anderson in 2004 when describing a strategy used by Amazon.com and Netflix.

When Long Tail marketing is used, large numbers of pages are created, each one targets a large list of keywords related to your product or service.

Google seems to give more weight to sites based on the overall body of a sites content. The more quantity and quality of content the better they think your site is.

I have not quantitative results to back this claim up, but it is based on anecdotal and real world observation.

If you are aware of any studies or research that demonstrates this