... it doesn't follow that because authorities are unreliable, their assertions without supporting evidence should not adjust your weighting in belief on any specific claim?
That's a strange world-view you have.
It is not so easy to separate assertions and evidence, Logos01. An assertion is in itself evidence - strong evidence perhaps, depending on who it comes from and in what context. Evidence is entanglement with reality, and the physical phenomenon of someone having said or written something can be entagled with what you want to know about in just the same way that any other type of evidence is entangled with reality.
For example if you were to ring your friend and ask him for the football results, you would generally update your degree of belief in the fact th...
LessWrongers as a group are often accused of talking about rationality without putting it into practice (for an elaborated discussion of this see Self-Improvement or Shiny Distraction: Why Less Wrong is anti-Instrumental Rationality). This behavior is particularly insidious because it is self-reinforcing: it will attract more armchair rationalists to LessWrong who will in turn reinforce the trend in an affective death spiral until LessWrong is a community of utilitarian apologists akin to the internet communities of anorexics who congratulate each other on their weight loss. It will be a community where instead of discussing practical ways to "overcome bias" (the original intent of the sequences) we discuss arcane decision theories, who gets to be in our CEV, and the most rational birthday presents (sound familiar?).
A recent attempt to counter this trend or at least make us feel better about it was a series of discussions on "leveling up": accomplishing a set of practical well-defined goals to increment your rationalist "level". It's hard to see how these goals fit into a long-term plan to achieve anything besides self-improvement for its own sake. Indeed, the article begins by priming us with a renaissance-man inspired quote and stands in stark contrast to articles emphasizing practical altruism such as "efficient charity"
So what's the solution? I don't know. However I can tell you a few things about the solution, whatever it may be:
Whatever you may decide to do, be sure it follows these principles. If none of your plans align with these guidelines then construct a new one, on the spot, immediately. Just do something: every moment you sit hundreds of thousands are dying and billions are suffering. Under your judgement your plan can self-modify in the future to overcome its flaws. Become an optimization process; shut up and calculate.
I declare Crocker's rules on the writing style of this post.