Forgive my candor, but if you think 13 returns is worthy of "
there you have it", your grasp of statistics needs a serious upgrade.
Did you happen to watch the preseason, by any chance? Did you notice when Gunner was noticeably more decisive and athletic than the guy most assumed would take the position? Or perhaps see his 9 returns for 122 yards, which is a tidy 13.5 average, made even more impressive by the fact that it wasn't inflated by a single long return? Did you notice that he took such a firm grip on the position that Berrios didn't even have a return the last couple games?
Granted, it's the preseason, but when exactly is a rookie supposed to have made the biggest impression? Am I supposed to conclude after just three games that none of the skill he displayed for the prior two months is legitimate? Frankly, his biggest mistake - other than the fumble, of course - is trying to do too much with return that aren't really there..... which, coincidentally enough, is the primary driver of the low average you amusingly attribute to athleticism.
It seems our battle lines are drawn, now let's see how Gunner's season plays out.