Its a very interesting question and it seems likely to me that to me that the tests done by Rand it the 1st article and the ones in the 3rd are right. I think I will do my own similiar test as well.
I can think of many of my own sites that need to be looked at with this in mind. The text in the menus isnt always the best anchor text due to many reasons: useability, space etc. One thing I may try is a css 'footer menu' with the phrases I really want as anchor text that is at the top in the html but displays as the footer. This wouldn't be considered 'bad' manipulation of se's would it?

I wouldn't be game to try nofollows in the menu links on any of my sites except one specially used for testing.

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Aussie SEO chick Kook Multimedia: Sunshine Coast Seo