I imagine there are UI design best practices, like watching new users try out the site, that could be followed. A similarly serious approach I've seen is having a designated "help out the newbie" role, either as someone people are encouraged to approach or specifically pairing mentees with mentors.
Both of those probably cost more than they deliver. A more reasonable approach would be having two home pages: one for logged-in users that probably links to /r/all/new (or the list version), and one for new users that explains more about LW, and maybe has a flowchart about where to start reading based on interests.
So the homepage already explains some stuff about LW. What do you think is missing?
I'd guess we can get 80% of the value of a flowchart with some kind of bulleted question/recommendation list like the one at http://lesswrong.com/about/ Maybe each bullet should link to more posts though? Or recommend an entire sequence/tag/wiki page/something else? And the bullets could be better chosen?
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