Yes it is, by the "filter" is not.
Yes and no. As I constantly add content pages some pages went up while others went down, overall we did well. Yes our site is a commercial one and yes we sell software, so the "money terms" theory doesn't wash with me either.
I don't waste my time. I would rather focus on adding content than running around in circles. There are 3.6 billion pages so any 'good' testing would take FAR too long and probably still prove little.