I think it is more in context of the individual opinion. The polling could determine an answer, but it would be based on people's experience of the cannoneers in action. For example, since joshly plays as a cannoneer in both US and European servers, he would be known by more people for his skills, whereas me, a new player to the community who only really plays on US, would not be able to show the European players my level of skill. Since nooone outside of the US servers would see me shooting, they would not have an opinion of me to judge whether or not I am better than Joshly, and so on.