Why? Because Politics is the Mindkiller. Once a belief is identified as a belief of the enemies, defending it makes you perceived as defending the enemies.
Aaaaaaaaaaand because espousing such a belief probably means you are "the enemy", that you're a reasonable person who came to the same conclusion (and didn't have the sense to introduce it in a more effective way) is probably much less likely.
That's pretty much the same point I made in a different thread
By correlating X with Y (where e.g. X=race and Y=average intelligence), other people end up correlating "People who correlate X with Y" with Z (Z=people who are evil racist bastards).
That's a proper correlation, but it's still a epistemological bias to prejudice against the idea, just because the speakers of that idea are often evil.
The talks from Skepticon IV are being posted to YouTube.
So far we have:
ADDED:
More to come soon, hopefully...