An experienced painter, giving an estimate for painting our house both with and without removing the paper, told me that if we wanted to do that part ourselves, just peel off the top layer (which came off easily with ours) then spray or sponge on “the hottest water you can stand” and work the bottom layer off with scrapers, then wash the wall well. Using heavy rubber gloves greatly increases the temperature of “the hottest water you can stand” and thus the effectiveness of the technique. No scoring, no solutions, just hot water. It works. I let it soak in a while, 10 to 15 minutes per area (being an old woman, I did about a 4′ x 4′ at a time and let my son do anything requiring a ladder), then used the plastic putty knives to work it off. Some areas were tough even with this, but 95% just took a little effort, nothing too daunting even for hands beginning to feel the aches of arthritis.