I can see why one would want to merge websites—one fewer Wordpress instance to maintain, if nothing else. I would guess hpmor.com passed the peak in terms of pageviews years ago, and it might make less sense to keep it as a standalone website now.
If maintenance were the rationale (which is perfectly reasonable), they could have just dumped the static HTML and called it a day. It’s not like the site changed or had any special interactive or dynamic aspects. (And such an archival scrape would likely have been substantially less effort than this special integration has been, and will be, I predict.)
I can see why one would want to merge websites—one fewer Wordpress instance to maintain, if nothing else. I would guess hpmor.com passed the peak in terms of pageviews years ago, and it might make less sense to keep it as a standalone website now.
I wish redirects were handled more granularly, though. https://www.hpmor.com/chapter/1 should lead to https://www.lesswrong.com/s/PtgH6ALi5CoJnPmGS/p/vNHf7dx5QZA4SLSZb and https://www.hpmor.com/chapter/2 to https://www.lesswrong.com/s/PtgH6ALi5CoJnPmGS/p/6L523aJDpjm4yWxue rather than to the top page. Cool URIs don’t change.
Also, it looks like pages outside of the main content were not transferred. e.g. http://www.hpmor.com/notes/
If maintenance were the rationale (which is perfectly reasonable), they could have just dumped the static HTML and called it a day. It’s not like the site changed or had any special interactive or dynamic aspects. (And such an archival scrape would likely have been substantially less effort than this special integration has been, and will be, I predict.)