Robert_Charlton - 8:35 am on Nov 7, 2004 (gmt 0)

Also, there's nothing that says that Hilltop had to be implemented precisely according to the original papers. :-)

This thought has occurred to me a number of times. Could it be that Google is applying some sort of affiliation filter, but it's using a variety of affiliation tests... not just an A to B, B to C thing?

The Google "Similar pages" results, which I believe classifies pages with common inbounds, could be further cross referenced and/or also correlated with hosting criteria, cross-linking, etc, and perhaps also weighted relative to the number of independent links ("clean" inbounds not traceable to a common source), and you'd have a measure of affiliation that certainly applies to some sites that I've seen drop like rocks.