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The Washington Redskins' Week 1 starting quarterback has been the NFL's biggest turnover machine over the past two seasons. And, yes, Robert Griffin III has nothing to do with it.

Griffin's ongoing concussion drama means that backup Kirk Cousins will start the Redskins' regular-season opener against the Miami Dolphins. While that decision might generate relief from weary fans, it's important to remember what Cousins has done in substantial playing time since the start of the 2013 season.

In 575 snaps over 11 games in that period, Cousins has thrown 16 interceptions and lost four fumbles. In other words, he has committed a turnover about once every 29 snaps, or 3.4 percent of his plays. According to ESPN Stats & Information, that's the worst rate among 46 quarterbacks with at least 500 snaps during that span.

The details are in the chart. Cousins has paid for more mistakes than the lampooned Matt Schaub, Christian Ponder and Jay Cutler, among others.

As the backup to a struggling starter, Cousins naturally has evoked hope and excitement. That sentiment also was built on an intriguing but brief three-game appearance as a rookie in 2012. But the longer he has played, the more he has exposed himself as a backup-level player whose biggest flaw is what coaches hate most: giving the ball to the other team.

The Redskins don't have a choice in sidelining Griffin, but Cousins' apparently clear priority over third-string quarterback Colt McCoy is worthy of further inspection. We don't expect Pro Bowl production from backup quarterbacks, but it's fair to hope they can run an offense without handing the opponent a victory. The Redskins have won only one of Cousins' eight starts during the period we're discussing.

It's not hard to figure out why.