I have also found that being able to speak bluntly and off the top of my head about what I believe to be true is enormously valuable for me in truth-seeking. Having friends and forums where that is the culture is immensely valuable. Yet learning how to not do that - how to use my "polite pen" - has also been immensely valuable to me in getting my ideas across to a broader audience.

Each has it's place, and I think what most LWers need to hear is the point in this post, but I think it would have been clearer if all the examples were from the workplace / regular life. Then it wouldn't have had this challenge to LW culture you perceived.