I just found an article on the deleted MSM links which claims that some AP stories on NYT are not archived. They simply get deleted after 24 hours. The quote is in this story:

http://heatst.com/politics/deleted-article-about-a-norwegian-pedophile-ring-ignites-conspiracy-theories/

Here's the relevant quote:

According to the senior editor of standards at The New York Times, some AP wire stories are only live on their site for 24 hours. They basically have a running feed of AP stories on the site that editors rarely pay attention to and are cycled out without being archived.

When an AP article on The Times has “aponline” in the URL(like it does in the Norway piece), it is not archived on their websites.

ABC News and The Washington Post have not returned a request for comment by publication time, but they most likely have similar unsexy answers to the deletion.

Can any of you autists out there answer whether this is why these vanished down the memory hole? It's certainly plausible.