According to this german SEO site (its very trustworthy) Google has some serious issues with the anchor text handling.
As you may know, the anchor text is quite important for links. Probably even more important then the title of the actual page.
But if a page links more than once to one other page and uses different anchor texts, then only the first one counts! See the tests on the site above (screenshots).
I think this is really important when it comes to site navigation, as that normally comes before the content, and therefor before probably better anchor texts!
Now you really wonder why Google is handling it like this, but as I mentioned before, they seem to have some problems with their reality check. 😉