I have both. Reached to get Witten (and felt good about it). Picked up Davis in the very last round, in part because I'm a homer. Now I'm as happy as anyone that Davis had a great game last week, and I know he's playing the Rams this week. But are you taking crazy pills brother? As a 9er fan I would love to see Davis put up better numbers than Witten all year. But, until further notice, if you're looking to win in fantasy you DO NOT BENCH JASON WITTEN, not even for VD.
Oh also... water is wet.