Yes, the Jags could snipe them from other teams' practice squads at anytime without penalty or compensation to the other team, as the practice squad guys are basically free agents practicing with a team.  The disadvantage of sniping a PS QB, if you need one at that time, is that they have no familiarity with your playbook or teammates.  I think Dave will add a QB to the PS, so a QB one snap away from being the primary backup can become familiar with the offense (and provide a practice arm for drills when needed).  I am guessing Tuel at some point.  

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