I'm not a fan of this at all. Geno has been weighed and measured, he's spent years playing in the NFL. Geno is a backup tier player. He has a place in the NFL in that capacity, but as a starter? We know what he can do.
I really think Pete needs to role with Lock. I do think that Geno won the competition fairly. Geno, clearly is the more refined of the two as a passer. Lock pre-determines where he's going to throw the ball and stares down his receivers. Lock also missed some really basic blitz recognition. Geno was put in the very same circumstance, identified the blitz and shifted the protection.
That being said, Lock has more physical skills than Geno and he's younger. He's going to lose you more games in the short term, but that it's worth it to see if you can get anything out of Lock.
I personally don't think Lock will ever be very good, but at least he's young and has elite physical traits. A team like the Seahawks is not going to be competitive and because they're not going to be competitive, they need to go with the young gun.