The bellwether of a bad but possibly technically interesting HN comment is one that begins with a humblebrag: "One time a Fortune 500 company hired me to re-write their entire web tier using Django" or "last year, for fun, I wrote a fully-functioning TLS implementation in node". Such nonsense (or at best, unneeded information) is intended to provide credentials so that the reader will take what follows more seriously…
For most, perhaps it's a bit of both. And is that a bad thing? Is there something wrong with asserting your right to wield a technical opinion while also showing off a thing that you're proud of having done?
On the other hand, if I had prefaced that opinion with the following , it would be been a bit over the top:
I've been reading comments for years. Not just on HN, but all over the Internet. In fact, once I spent 60 hours in a week, just reading comments.