I suppose I misinterpreted. When you said going "back pages", I took that to be using the back button rather than clicking a previous page.
I take your point now, but I don't really think I agree with it. The implication is that you'd be reading backwards post by post, but I'm not sure that's necessarily how people would use it. Going to the start of the page is by far the most common behavior and I think it makes sense to maintain that.