I would call “moral progress” the process whereby a society's behaviours and their CEV get closer to each other than they used to by.
That's actually the best definition of "moral progress" that I've seen. A big step up from "more like the values that I currently wish to signal having", the default definition.
People on Lesswrong saying their CEV includes X or leads to Y, are not using the term technically but as a poetic way of saying X and Y look about right to me and I'm confident I'm not wrong. Substituting that into the definition makes it much less impressive for human use. And if you check writing on CEV you see the definition is nearly circular for technical use in FAI design.
Here's the new thread for posting quotes, with the usual rules: