From what I have seen playing in NA-servers I would say Waradin is right, I really mean it. I am mediocre at best when playing in EU-servers with ping of 40. Playing in NA I often have better score with a ping of 150-170 - lagging. Also from the few stratbattles I have been into in NA the overall performance of the players there are way below EU-standard. This could ofc be just luck for me, or it could be that I have only been fighting bad players out of pure chance.
Im sure that there are great players in NA - no doubt about it, but the overall player has, from what I have seen, lower skills than the average EU-player. This is true especially to blockingskills and ranged I think - generally speaking ofc.