Of the 12 kickoffs he ran out of the end zone, here's a breakdown on how deep they traveled:
Minus-5, minus-5, minus-3, minus-2, minus-2, minus-2, minus-2. minus-1, minus-1, minus-1, zero, zero.
Now let's project by adding on five yards for the kickoff: How many of those 12 would become touchbacks? You'd have to say anywhere from three to seven. That should give you an idea of the new rule's impact; we're talking about five fewer returns, give or take, for Smith.
On the whole, we are talking about one kickoff less than every three games. That is not very much. It is trickier than that, though. Return men will get the ball five yards deeper than they usually do, potentially cutting five yards off a number of returns. This new rule will also make it easier to execute deep directional kicks on plays that attempt to make the job of the coverage unit easier.
And although the touchback thing does not sound significant on the whole, but it could make a huge difference on individual plays. Add an extra five yards to the final kickoff in the Wild Card game in Indianapolis, and Antonio Cromartie catches the ball six yards deep. He might have had to take the ball out to try and break a big one no matter what, but you never know.