Cesc does provide assists and he scores goals. But his special qualities lay outside the standard measures. These players have an understanding of football that is beyond most other players. They can go cold when everything around them is hot. They don't feel pressure. They don't see danger in receiving the ball in their own third in tight spots. They can see a game and read a game and understand the tempo. And they usually have incredible awareness of what's around them. They see passes that others can't see. The comfort blanket they provide is to make team-mates believe there's safety on the ball when they're in possession.