Just a guess on my part, but I'm pretty sure his main priority is to start as a QB.  But you're right in the fact that he is already 26 years old, so maybe 4 years for cheap is limiting his upside.  Maybe they'll do something with roster bonuses that escalate over time, something like $4 million signing bonus, with salaries of 2M, 4M & 4M roster bonus, 5M, 6M with another $8M in roster bonus for the last two seasons.  But even those numbers a heck of a risk for a guy that's only played 2 games.

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