Am I right to think that a 'click-through' is a record of a viewer reading a page, and clicking a hyperlink to another page on the same site? So if I work through a menu system to get to sub-pages these actions will be 'click-throughs'?
It's been suggested Google is interested in these actions since it shows the site contains lower-level material which is of interest to the viewer. I realise that Google knows you've selected a site from its index of sites (sonce you click on Google's proposed site entry), but once you've downloaded the main page how can Google tell you're later requesting sub-pages? Isn't this a transaction solely between your local PC and the server supporting the page of interest - and with no remaining link to Goolge?