One method that I have used quite sucessfully in my 1920's house - sand
the wall down so there's no obvious lumps or depressions - fill as much
as possible and sand down etc.

Then use lining paper paper the wall horizontally - wait until dry,
then paper again, this time vertically.

You may find that it's quicker and will give better results than
sanding/filling/sanding/filling etc etc!

Good luck!

Simon

Oliver (R-e-m-o-v-e) wrote:
Having just done a whole house which pretty much similar surfaces I came to
the conclusion if the walls are really bad then geta pro to skim it for you
fro the other walls, patch it up sand it paint it then you will see more
bits that need patching areas that catch the light so then fill and sand and
paint again, takes a while an may be a botch job but does come up looking
quite good. Oh and a good quality paint for new plaster worked quite well