College football has a new rule this year, and there’s a lively debate going on about it. Teams will now kick off from their 30-yard line. Some coaches, Joe Tiller of Purdue in particular, predict the rule will mean more runbacks, and therefore special-teams players more often smashing full-tilt into each other, and therefore more injuries. But the rule’s champions predict it will cut down on all those b-o-r-i-n-g touchbacks, and that it’ll do something about the length of the games.

The question is, what? According to Sunday’s New York Times, one reason “for the change was to cut back on the number of touchbacks, which lengthen games but do not take time off the clock.” According to the AP, “NCAA officials expect the kickoff returns to make the game last a bit longer.” According to Vanderbilt coach Bobby Johnson, the rule was intended to do the first but will probably do the second: “The rationale was to speed up the game. It’s not going to speed it up because there are going to be a lot more kickoffs.” 

True enough, touchbacks take no time off the clock. Runbacks do take time off the clock — they take the length of the play off the clock. A five-second runback will take five seconds off the clock. Isn’t that a wash? What am I missing?

Johnson’s probably right that the games will get longer, because of the principle of unintended consequences. And Tiller’s probably put his finger on why they’ll be longer yet — it takes a while to immobilize a player’s head and ease him onto a stretcher.