Peterson gives them the tool they need to win games. He also gives them the tool they need to cover for Christian Ponder.
At this point, there is no other way to say it—Ponder is a liability.
I'm not saying the Vikings should ditch him, replace him or give up on him. You want to give a quarterback a few years to develop and really Ponder is only a year-and-a-half into his tenure as starting quarterback of the Vikings.