Mobile QB = Good
Running QB = very bad
Just ask RGIII or Vick etc.
The only important position in FB is QB. The more times you get hit the more likely you are to get hurt. Considering they're are probably less than 10 legitimate QBs in this league do you want the one piece of your team that will decide if you win a Super Bowl running every game?
QB mobility is primarily to NOT get hit...not to gain yards.
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