[nosianu]

> I've found the ones on HN seem to be more tolerable because they typically know they'll have to back up what they're saying with facts (and ideally citations).

Can you back this up with data? ;-)

I see citations and links to sources about as little as on reddit around here.

The difference I see is in the top 1% comments, which exist in the first place, and are better on average (but that depends on what other forums or subreddits you compare it to, /r/AskHistorians is pretty good for serious history answers for example), but not in the rest of the comments. Also, less distractions, more staying on topic, the joke replies are punished more often and are less frequent.