I have found that I'm always most disappointed in the comments in areas that I know something about, and I rarely comment on such article (luckily it doesn't happen that often). To be fair though I don't see HN as some kind of authoritative information source, it's just a place for somewhat like minded people to come and shoot the shit about stuff. So people have some dumb opinions about cars, they just want to talk about it, they're not writing legislation or something. It's like overhearing a conversation in a coffee shop, you can walk over and tell the people they're wrong, but my experience is that rarely leads to any kind of comeaderie. Better to just take part in the conversation and not worry if people are wrong (not that I'm good at following my own advice)