 Hilleman described it as a judgment call. It's guts and judgment. It's just absolute trial and error. I mean, there's no formula for this. It's not written down anywhere. You just try. And Offit told us. He really just had a sixth sense for how one did that. You know, different people would make different choices about that. And he's good at making the right set of choices. So you don't want it so chickeny that humans don't recognize, like, you know, a human body doesn't recognize it at all. But you don't want it human-y to the point where.