Like I stated I cant prove anything and am just speculating but my groups are not a one day one occurance thing. The rifle has been shot by myself and others with the same results. Most of the others are better shots than myself and none have posted much better than MOA at 100 yards, some have posted much better than 1/2MOA at 800 yards. All of us know how to adjust parallex. I can only go by my experiances, but that is what appears to be happening to me. Here are some links to two threads from another site that has some people more knowledgeable than myself with similar thoughts on the matter. I think I also saw some similar threads over on BR central and 6mmbr also, most seem to take it as fact also. Good luck finding answers.

http://www.longrangehunting.com/forums/f28/how-do-you-lower-s-d-27589/

http://www.longrangehunting.com/forums/f19/bullet-stabilization-myth-29611/