tedster - 7:55 pm on Apr 30, 2011 (gmt 0)
I never found that hack to be all that useful. Matt Cutts once said it was a query that tripped a kind of error routine and caused the URL retrieval to stop part way, but there is no certainty about where that "stop" actually occurs. It apparently does retrieve the most core page first, but it's pretty rough - the retrieval process might stop before it taps any supplemental partitions or after it grabs some, or whatever.
I think it's more informative to do the site: operator on AOL and see how many URLs Google feels are essential enough to export to their partner.