Someone affected by the issue might bring up something that nobody else had thought of, something that the science and statistics and studies missed - but other than that, what marginal value are they adding to the discussion?

Thinkers - including such naive, starry-eyed liberal idealists as Friedrich Hayek or Niccolo Machiavelli - have long touched on the utter indispensability of subjective, individual knowledge and its advantages over the authoritarian dictates of an ostensibly all-seing "pure reason". Then along comes a brave young LW user and suggests that enlightened technocrats like him should tell people what's really important in their lives.

I'm grateful to David for pointing out this comment, it's really a good summary of what's wrong with the typical LW approach to policy.

(I'm a repentant ex/authoritarian myself, BTW.)