tedster - 7:37 am on Feb 28, 2011 (gmt 0)
Yes, it does make sense, but I don't see evidence of this in practice - got data? What I see is Google not keeping weak pages in the index, but good pages can still rank even if there are only a few.
There are some kinds of sitewide factors in play - Matt Cutts made mention of them several times. But I'm not zeroing in on what they are. Even this new Farm update seems to be executed page-wise, and not site-wide.