Hi All, just got back from Cadbury's world. I will try and explain what i meant by my earlier comments.
First off, apologies for the hastily drawn graphic
Site structure. In its simples form when building a site think of how you build a house of cards (HOC) (bad analogy I know, but structure wise it is right)
Say there was a house of cards, 3 on the bottom then 2 with 1 little triangle on top. If you asked people to point at the most important triangle, they point to the top one! (1) fig 'A'
Now hold that thought, build another identical HOC next to it (2) . We now have TWO equally important triangles, 1 at the top of each HOC.
NOW imagine you placed a piece of rigid card between them, and built another HOC between the two, but only one single triangle (3). So now you have 2 HOC's supporting the one above it. fig'B'
NOW when asked to point to the most important one, you ignore the two you previously pointed to, and immediately point to the one at the very top.
Take it further and add more single triangles below (3) but with no triangles below them fig'C' . Now point to the triangles in order of importance, and you will think that 3 is the most important followed by 1&2, probably followed by the triangles with no numbers, and lastly, 4.5.6 &7.
Same with well structured sites. Each HOC represents a folder, each of those card that built the HOC represent web pages on the topic. The page at the top of each HOC is the most important for that topic (index page where all the other pages in the folder link to.)
Pages within the folder will cross link with each other, but rarely with pages in other folders, but ALWAYS to the index page of their folder, and the main site index page making IT the most important on the theme of the site.
This is what creates the correct hierarchy within the site, it is how link juice flows within the site, and it helps to sub niche areas within your site. AND, once you become an authority for a phrase, it will be the main index pages that become your sitelinks on a Google SERP
Now if your site is about cars. and uyou have a folder for each manufacturer, and within that folder you have models, and below them you have repairing / history/ photographs etc. Then the page the search engines return might be the homepage of the folder that houses all that information about the XJS, BECAUSE it is in a folder about jaguar, and is cross lnking within that folder conrtextually to semantically related pages.
This WAS to be a blog post, but looks like I have just scuppered my doing that

I might blog it though and then link from here.)