airplane down?

You don’t want to be on the plane that has a 32% accuracy. You want to be on the plane that has the closest to 100% as they come. Single parent families statistically do not produce mentally healthy or successful kids. “Normal” families (Santorun’s normal) have a much higher success rate. The analogy is illustrating that normal families work better and therefore should be promoted.
Santorum in this article does admit that non-normal families can be successful, but I don’t think he talks about it enough. Of course he does this on purpose to make sure his point is the obviously better one, but I still think it looks like because he glossed over this it shows that he knows there are many successful non-normal families but doesn’t want to admit it. I think he should have spoken about it more to show that this is not what he was doing (but perhaps this is what he was doing?).