Back From A Breather II, Ctd

A reader writes:

I think that Ms. Palin is handling the matter perfectly.  Why in Heaven's name would she fulfill what you call her "burden of proof"? Why would she "clear up a question for which there must be a mountain of readily available medical records"? The political calculus - one that seems entirely accurate - is that she does not benefit from proving that she is Trig's mother and that she benefits from refusing to prove that she is Trig's mother.

If she is not Trig's mother, then any...