A couple months ago I was thinking about some stuff related to moral rules for simple simulated agents, googled a few relevant keywords and the first reference was someone referencing a 2004 blog post of mine about the first book in your list, Artificial Morality. The thing is that I have no recollection reading that book, even less blogging about it, and that was years before I started reading Overcoming Bias. Even rereading my old post didn't help me remember. And my blog has been down since maybe 2006/2007 (not that there was anything worth keeping there).
It's a bit scary to follow a line of thought, and then find out that you already thought that years ago and totally forgot. I guess a human made immortal would get that feeling all the time.
I had a similar, but less extreme, version of that the other day. I was reading an unfamiliar thread from 2010, and I wanted to upvote a comment, but I saw that I'd already upvoted. That was confusing. It happened a couple more times, and I wondered when I had done that. I couldn't remember ever having been to the thread before. Then I saw some comments I wanted to reply to--complete with replies from myself, saying similar things. That was finally enough to jog the memory of the last time I'd read the thread, but it was still a surprise. My opinions, or at least my way of expressing them, had changed a little, but I got the same sense of deja non-vu you did.
Timeline: