Here's what I started with (Holes in wall are from electrical crew fishing new wiring--back in 2005. Yes, I've been living with holes in my walls for far too long, but that's another story.)
I took the top layer off and found just one layer underneath (oh thank GAWD).
Underneath this was bare plaster in lovely condition (oh thank GAWD again!). Now I started getting a little confused. The house is circa 1875-1880, but the original layer of wallpaper sure doesn't look like a Victorian pattern to me. I decided to save a little square of it to frame on the wall just for fun. I kept up with my scraping and the plot thickened. The bottom half of the wall was painted brown underneath the bottom layer of wallpaper. WTH?
I did a little investigating in the electrical access hole, thinking maybe they had skim-coated the wall at some point after the initial paint or something, but I found no evidence of it, and there's no difference in grade between the paint and bare plaster. I say again, WTH?