Here's an analogy that works for most people, but maybe not Slashdotters, as it involves talking about girlfriends (use "My Guild is the best and undefeatable" as a substitute)
You claim your girlfriend is 100% trustworthy.
When some jerk thinks you're wrong, and decides he wants to hit on her, you throw a fit saying any doubt can not be tolerated. (Instead, let him publically embarass himself, and show him how its really done when he goes down in flames)
When someone shows proof she's been texting her ex, you throw it out (though, if you looked into it, you might find a good explanation: you might find she was just trying to get back her hottest lingerie to wear for you, or she wanted the phone number of the smoking hot babe she told him no about, but she wants the threesome with you)
If you are confident, these things aren't a problem.
And though I think they are likely correct about their conclusions, their lack of WELCOMING contrary points of view makes this the issue.
Though I will never claim to understand all of the science, I can see immediately their fear of even being questioned.