All of this is laid out, with much greater detail, in her blog post on the topic here. It is very, very much worth reading. She illustrates that a person's ardent belief, up to and including a willingness to die for that belief, does not prove the validity of the belief (there's a tremendous logical and factual chasm between"I believe x" and "x is true"). But far more importantly, she shreds the premise on which the whole thing is constructed -- that someone will not die for something they know to be false.
People will die for a lie, either because of coercion or to spare a loved one.
And, beyond that, though, people will die for a lie based on voluntary false confession for a number of reasons, as scientists have already established (seriously, read the post. It's all laid out there): a compulsion to suffer as recompense for a wrong (imagined or real), a desire to profit, the thrill of it, etc.
I don't have much to add to that because Tracie's points are amazingly thorough and well documented. There is one aspect that I would like to spend a little more time on, though, and that is religions motivations for lying. She touches on the topic, with her characteristic wit and wisdom:
Would a Christian saint lie, though? Someone so devoted to god? Absolutely, yes, if they were suffering from these issues. Good Christians have lied without gaining notoriety, redemption, or a rush. Every scribe that ever doctored a canon text to make it a little more orthodox is guilty of lying for the cause of Christianity. I’m sure they were aware it was dishonest. But a higher cause, a nobler goal was prompting them. The texts were revised. We have the notes in our Bibles today describing which passages have been added or altered from older or better manuscripts. Quotes were “fixed.” Characters were made more consistent or gentler. But it was all to improve on the message—all for the greater good.I would add only that this precise mentality of lying to further your religious beliefs, lying to further causes religious people consider greater than themselves, spawned the term "lying for Jesus". Simply put, many religious people will lie if they think it furthers their argument or beliefs. And it's not a new concept. Fourth century bishop Eusebius advanced the notion "that it will be necessary sometimes to use falsehood as a remedy for the benefit of those who require such a mode of treatment". In other words, lying is acceptable if it's for the greater good. Furthermore, an obsession with martyrdom is a feature of Christianity and Islam. We know that people will and do die for their gods (radical Islamic teachings often laud religious martyrdom as a magnificent goal; indeed, it is marketed toward children as such; and Christianity for its part is obsessed with the persecution complex). In combination with the guilt that religion imbues, and the martyrdom obsession of both Islam and Christianity, is it farfetched to think that someone might see martyrdom over a lie, all to aid a cause greater than themselves, as a worthy goal? Of course not. Religious people will and do lie, murder and die for their faiths, in combination as well as individually.
Yes, people who subscribe vehemently to a doctrine will lie and die for it—even if the doctrine promotes honesty as a virtue. It’s weirdly hypocritical and contradictory—but since when have religious zealots (or any of us, for that matter) been immune, as humans, from hypocrisy or contradiction? Aren’t these, ironically, some of the very flaws Christianity says we’re all subject to? On that note, how ironic that an apologetic would be built around the idea that a human being couldn’t possibly act in a way that makes no sense. We see it all the time. The Bible condemns us for it and calls it sin and fault. I call it being human.
Would a reasonable person die for such a lie? No. But since when are humans—even most humans—reasonable? Where in the world was that fantasy bred?
Claiming that a person's martyrdom is evidence of anything beyond their commitment to a cause (and that, as Tracie points out, is not even always the case [if coercion, etc., is involved]), is ludicrous. It's an appallingly bad argument, that fails on just about every level -- starting with its premise.