It seems like you have several separate things in mind: readability, information density, arguments masquerading as true causes of beliefs, trustworthiness of "experienced rationalists," and the value of the "main point" vs disclaimers and qualification. Do you have an example post in mind, and specific suggestions for an improved version? I'm not sure if I'm about to respond to you, or just ramble. I understand that it's hard to call someone out without being mean, but these meta discussions seem to go nowhere without specific examples. (That said, the rest of my comment is not any better in this regard. Also, feel free to use any of my posts or comments for target practice.)
I agree that LW falls short on readability. Most people, LW posters included, are not good writers to begin with. Conciseness is one absent virtue among many. On the other hand, extremely information-dense texts can also be unreadable. Also, conversational, forceful, and polemical styles -- which are easier and more entertaining to read than academic styles heavy with caveats -- accompany lower epistemic standards. It's possible to be highly readable, informative, and rigorously correct, but it's hard. Littering your claims with "I think"s and "probably"s is a poor solution. Even if your main worry is coming off as too authoritative, such ugly filler qualifying language can be replaced with specific qualifications, possibly in a preface or footnote.
Your "murder is wrong" example is a poorly-constructed sentence, sure, for reasons beyond the above. But the details and qualifications are the real content of that statement. I don't think that's because "murder is wrong" is an uncharacteristically content-free claim. For any basic principle or sweeping generalization, there will be cases where it obviously works, cases where it obviously doesn't, and the real information is in where you draw the line. (And that statement applies to itself. I may need to elaborate in a separate post.)
I already see over-reliance on simple/abstract/principled arguments and beliefs as a weakness of LW discourse. This is a shame, because people here should have a huge advantage in terms of consequentialist reasoning and the ability to recognize and discuss tradeoffs without knee-jerk responses.
Regarding your other points, I agree that people often present arguments which do not include the true causes of their beliefs, and that this is bad. I also (relatedly) have enough confidence in very few people here such that a mere statement of their beliefs would be informative.
You're right, there's multiple related points to be made here. So, let me try to clarify the issue a bit.
If I write a post with specific examples, people will get too hung up on the examples and the main point is lost.
if I don't post examples, people will comment that I am not specific enough.
If I state very clearly and succinctly what I mean, there's the risk that I come across as arrogant.
If I quantify everything with disclaimers, the post becomes less readable and people won't know what I think.
If I don't anticipate every possible counter-argument, peop...
I like posts that are concise and to the point. Posts like that maximize my information/effort ratio. I would really like to see experienced rationalists simply post a list of things they believe on any given subject with a short explanation for why they believe each of those things. Then I could go ahead and adjust my beliefs based on those lists as necessary.
Sadly I don’t see any posts like this. Presumably this is because of the social convention where you’re expected to back up any public belief with arguments, so that other people can attempt to poke holes in them. I find this strange because the arguments people present rarely have anything to do with why they believe those things, which makes the whole exercise a giant distraction from the main point that the author is trying to bring across. In order to prevent this kind of derailment, posters tend to cover their arguments with endless qualifications so that their sentences read like this: “I personally believe that, in cases X Y Z and under circumstances B and C, ceteris paribus and barring obvious exceptions, it seems safe to say that murder is wrong, though of course I could be mistaken.” The problems with such excessive argumentation and qualification are threefold:
By contrast, terseness makes posts more readable and makes it less likely that the main point is misunderstood. So if we as a community could just relax the demand for argumentation and qualification somewhat, and we all focussed on debating the main points of posts instead of getting sidetracked, then perhaps experienced rationalists here could write nice and concise posts that give clear and direct answers to complicated questions. Instead, some of the sequences are so long and involve so many arguments, counter-arguments and disclaimers that I feel the point is lost entirely.