I think it's fair to assume that people don't expect the article title to be changed after the HN submission.

But generally, I do wish fewer people moaned about HN titles. Even when the title matches the article, people often moan about it's grammer. In fact there was one submission last week where more people were discussing the title than were discussing the article. However I do appreciate the irony that I'm contributing to my complaint by discussing it like I am :)