I have done venetian plaster twice before...piece of cake, BUT I have a friend that wants to do their kitchen and NOT remove the wallpaper. There is no visible peeling and it is not textured. Has anyone done this before and if so, what were the results. I myself would just break the sweat and remove the paper, but I said that I would ask around for my friend.

That doesn't sound like a good idea. I've never heard of anyone doing it. I know that Doug had a room once with wallpaper, but they took it down before he plastered. I know of a couple of people who tried to paint over wallpaper and it always bubbled. You'd think that it would do the same thing with the plaster.