The dynamic quarterback is still a new and rare breed in the NFL. Most players with that type of athleticism gravitate toward receiver or running back rather than under center, but any defensive coordinator can tell you how much havoc they create on a defensive game plan.
It is undeniable, however, that a quarterback who relies as much on his legs as much as his arm has had limited playoff success. Dating back to Randall Cunningham - who most refer to as the original dynamic quarterback -they have a history of being good. But not great.
Michael Vick set the world on fire in Atlanta when he burst onto the scene in 2001 with the legs of Barry Sanders and the arm strength of John Elway. A lack of accuracy and a "run-first" mentality, however, hindered his success in the playoffs, going only as far as the NFC championship game in 2004.
Some quarterbacks in the likeness of Vick have made splashes in the league. Tavaris Jackson, Jason Campbell and Vince Young have come and gone, but none of Vick's caliber. Cam Newton and Robert Griffin III are the biggest threats to surmount Vick as the top dynamic signal caller in the league, but in my opinion, they are both a good case of buyer beware.
Being dynamic as a quarterback has its benefits. Steve Young, Donovan McNabb and Steve McNair both had solid careers and were known for being able to extend plays and run for a touchdown or a first down when they needed to. The key phrase there being "when they needed to." There's nothing wrong with using your athletic talents to make a play, but when it becomes your first priority and something you rely on, you can be a detriment to your team.
The best comparison is Michael Vick and Ben Roethlisberger. Vick is the superior athlete by far, but Roethlisberger uses his ability to extend plays to allow his receivers to get open, not to gain yards. Vick struggles with this. When it comes down to winning playoff games - playing against the toughest defenses - the quarterback needs to rely on his ability to pass the ball, not run it. Running should be a last resort, not a goal.
You'll get a lot of people arguing that dynamic quarterbacks are the future of the league, and that may eventually be true. Newton blew up the rookie record books last year and Griffin has his own internet meme by week two this year. Both are fun and exciting to watch, as was Vick.
Evolution of a position doesn't always happen overnight, especially at quarterback and especially when guys like Tom Brady and Peyton Manning - who couldn't run away from a fire - are still kings of the league.
The way I see it is if you have a quarterback who splits time between running and passing, there will eventually come a time when they can no longer choose between the two and become mediocre at both. Legs will inevitably wear down, and if the arm has not been developed, life is going to be hard. Just ask Michael Vick right about... Now.
I have yet to be proven wrong.