Im researching keywords and how tough the competition for those keywords are, and sometimes it seems just wayyy too easy.. Say its a best "product" searchterm and the serp shows 10 aff sites, keyword tools says its ~20 competition.. It obviously seems a bit off. I know you can hide pbns and backlinks with robots txt, is this what they have done? Since some sites have 1 PA and sometimes even 1 DA in top10, their backlinks must be hidden in robots.txt right? And if so, how could i analyse how strong their domains really are?