An interesting point. As it happens, when it was submitted 500 days ago it was a slower day (in some sense) than today. The "newest" page had fewer items per hour back then.
It's an interesting observation, though, that for some items the "value" changes over time. This particular item, I suspect, doesn't fall into that category. Context might be more important, but the analyses I do try to take that into account.
Eh, it's starting to sound like sour grapes again. There isn't an objective standard for value you can discover if your analysis is just a little better.
You're right that there isn't an objective standard for "value" (or at least, I don't know one, nor how to get one), but multivariate analysis can assign a number to an item which is broadly aligned with my intuition of the concept of "better". As a result, I'm trying to home in on finding items that my system predicts should be "of value" so I can read them, even if they don't make it to the front page.
Consider, I can train a Bayesian Filter with the page text of many submissions, and get that to predict what I'm likely to find "of value." But that means I don't see what the community might have found interesting but would be outside my core interests. These, too, are "of value" because they stretch me. I can't just train the filter with what makes the front page, because the evidence is that many things that "should" (by some definition) don't, and that would damage the training.
So it's complicated. I'm trying to find ways to improve the community and help me get more out of it (obviously) with less effort. I'm trying to help, but the hassle I get is just encouraging me not to make these observations out loud.
Based on this, your profile, and the rest of the comments in this thread I would suggest that whatever it is you're doing is vastly more effort than you're going to get back in added value.
It's an interesting observation, though, that for some items the "value" changes over time. This particular item, I suspect, doesn't fall into that category. Context might be more important, but the analyses I do try to take that into account.