I'm piecing together some stats here. According to this (http://espn.go.com/blog/statsinfo/po...-effect-on-nfl
), 1374 kickoffs were returned in 2011. So 10 scores on 1374 returns, that's roughly half the scoring of corner kicks. Of course that's playoff soccer, with the best teams. I assume that if you look at regular season totals that corner kicks would result in less scoring, as the overall quality of play would be lower.