So if someone wrote "Kate Upton is the best looking female in the world" you would consider that a "factual statement" subject to evidence. Maybe YOU need to work on your reading comprehension.
I have my reasons to think Sokol is the best leader (not that you REALLY care, I know). Nevertheless, leadership isn't a big factor, imo, like you seem to think it is. If you've been in a position of leadership you would know that leadership is 80% about the position you're in. In other words, people respect you if you are in a position of authority or leadership. Whoever gets the nod will be respected by the players and they will follow. That's guaranteed.
Now, to be an above average leader, you need confidence and ability. To be a great leader you need those attributes and vision. Steve Jobs, Bill Gates, George Washington, and Abraham Lincoln were all great leaders due to their vision. You have to project confidence to be a really good leader. Sokol is the only one who projected confidence through his mannerisms that I noticed and that's why I think he's the best. Again though, I don't think it's as important as you seem to think it is.