Whitey - 10:57 am on Mar 25, 2012 (gmt 0)
I certainly think Amit knows (really, any Google search engineer would) which signals are currently used and which are not.
My interpretation is that Ryan goes way beyond that statement. He say's he has "full ranking" knowledge.
.... would you extend that "knowledge" to any search engineer Bing , Google, in their obsevations of each other, having a "near total ranking knowledge" of each other?