That's all very logical, but it doesn't account for an angry plaintiff who's really not concerned about money.
We'll have to see how it plays out, but I tend to think a settlement relies on an insurance policy sufficient to cover the settlement demand. My guess is the insurance amount is not sufficient to satisfy the plaintiff at this juncture. So the lawyers let it play out, and if the plaintiff is angry enough, she could take it to trial just to hear the gavel fall.
Nor does it account for a defendant who is unlikely to ever agree or appear to agree that he did anything wrong, so I'm guessing is perfectly willing to gamble on a jury that agrees with him.