Thanks for the response and the reasoning behind your post and you bring up some valid concerns. This forum at least brings some meaningful discussion, unlike the main board.
My reasoning for Mettenberger is that I believe he is the best pure pocket passer in this draft. Big guy, big frame, nice release, has a cannon of an arm, and has worked in a pro offense this year under Cameron. He has improved leaps and bounds under Cameron and I like his ability to fit a ball into a tight space and IMO that is one of the most important aspects of QB play.
He's not the most mobile, as you stated, but he will tuck and run, and can roll. That's why I like him as a WCO QB and running the read option has zero to do with a WCO.
I dont disagree with your evaluation of mettenberger, which is why I think he will be picked in the top 100 even with his limited production and injury - he can certainly drive the ball.
I think when you are drafting a QB in the situation that we are, as well as attempting to build a team/organization, your backup needs to have a similar skill set to your starter. Matt Flynn didn't work in the raiders awful offense or fit in with buffalo (he just got beat out in seattle) but he was good in GB as he is a tempo passer, that can hit the short to medium routes similar to rodgers, just not with rodgers deep accuracy and overall level of skill.
I personally think Geno has + arm strength, understands the position as far as turnovers (he will get there - he threw very few picks in college, even Luck had 7 picks this postseason), can run, and cares about being good. I think he will be a good NFL QB, and this organization just committed to Rex, MM and Geno (whether Idzik admits it or not and whether we draft a QB or not) so we then need a backup that can fit seamlessly into this offense.
Personally I think aaron murray can be picked in the 3rd round and fit this offense pretty well - at least in 2015 while he recovers from his own ACL. He can move in the pocket, can drive the ball, and will need an offense that moves him as far as rollouts etc as he is shorter.
Hes not a guy who is known for accuracy in the short to medium range (58% comp in 2012 and 65% this year) but more of a joe flacco who is real strong in the pocket and can hit deep passes down the field with his arm strength. He also has virtually no mobility so any of the roll outs and read option plays we will be using with Geno will not translate to him.
In no way am I saying he will or won't be a good pro, but he doesnt seem like a good fit for a backup to Geno
I like Mettenberger. And he played a great game with Idzik watching him.