I am in the process of doing my kitchen and it had vinyl coated wallpaper (from the 1970's I'm guessing). I spoke with a painter and he said the best way to do it is:
1) Peel the vinyl layer off first (no need to score it or DIF it); this will leave the backing which looks similar to a brown paper bag
2) Take a spray bottle and use warm/very warm water and spray a couple areas; within 5-10 minutes you can scrape it or peel it off
3) Any remaining glue or adhesive can be removed using your chemical product and scrubbing it with steel wool