You are just an angry little man aren't you? First off, I didn't say he slipped, I said he messed up. I am no apologist for what he did. And regardless of what happened, it was a stupid mistake.
Secondly, yes it is an average, but let me give you a little math lesson. Say we have returned ten kickoffs. Eight of them for twenty yards and two of them for two yards. We have a 16.4 average. But as the season goes on, we have twenty more, for an average of twenty yards. That is 564 yards ... now we have an 18.8 yard average, a 2.4 yard improvement. It is just a matter of getting more reps to make up for those blunders, and that is why these "Ainge is leading the nation in QB rating" are kind of premature. Talk to me after six games. We will climb up that kickoff return list. And Ainge will come down some from the top of the qb list (I am sure he already has some after Saturday).