jimbeetle - 6:55 pm on Jul 8, 2010 (gmt 0)
so it appears to be a neutral third party link
And there's the rub. Network analysis is a very mature field and with Google's resources this can stick out like the proverbial sore thumb. In fact, when it comes to small networks such as this would appear to be they can be discovered by very determined eyeballs alone.
I heartily agree with buckworks and that enhancing the overall authority of the domain itself is what works for me. There's also a few-year-old Google patent out there that talks about "document grouping." I don't have it to hand at the moment (and am most likely paraphrasing wrong), but it's along the lines of a group of related documents being more powerful than the sum of its parts -- related pages supporting each other, more or less.
That's not to say that the "Theory 2" approach can't work. But that means much more work for you in trying to build *credible* support for multiple domains.