[David raises his eyebrows at the implications in that.]

Are you suggesting we kidnap a Winchester-protected nephilim, Harvey? Because I don't think that's the best use of our time.

[He has a feeling that the Winchesters will keep that handled for them, and it doesn't involve brainwashing a child, which is David's least favorite activity.]

As for how to prevent this from happening again, maybe we don't need to focus on the doppelganger so much, and make this hunter army more of a priority in resolving. And I think that might involve finding out where Allison Argent is going next. I'm willing to bet that would be their next attack.