Agreed, when I hit back once or twice I was like crap. (I had just scrolled through every one.) So I just opened a new tab to HN, and closed that tab. Poor tab.
We are on the same page(no pun) that back button should take you back to HN, but if you are on chrome, clicking and holding the back button (browser's) shows you the list of tabs and you can choose the tab from there.