This is a bad comment for Hacker News. We want to optimize for signal/noise ratio. It's good to laugh, and to upvote; reporting that one laughed, and upvoted, not so much.
I've often wondered about that, I know that in reddit and even slashdot these type of comments are lauded even though they add nothing to the dialog people like them, because well, they do do give us another comment to upvote, because you can add one point to the original comment. Still they deal with all that extra chaff by physically minimizing comments that don't get enough likes thus they don't interrupt the flow of conversation as much. HN doesn't have such a feature so I understand why, you're against it, I personally only downvote these type of comments if the user has a history and the comment is >2 words.
They certainly aren't English speakers. It's a pity because they've a really solid product, just not showing it off well to an international audience. The rest isn't full of mistakes as much as just being informal and inconsistent, I suppose it's quite a difficult language if you're not accustomed to writing it.
