'smoothing' normals in Blender?

I’d solve it this way :

  1. don’t split the face at the exact edges as you did, but include the skirt around the edges (1 row of faces is enough)
  2. apply a different texture to the skirt, eg. “DEL.jpg”

Once loaded to panda, you’d get 2 geoms (or more), the face geom, and the skirt geom.
Next, find that skirt geom by its texture (DEL.jpg) and remove it, so you’d end up with the face geom only, with the normals unchanged :

sp = loader.loadModel('SPHERE1')
gn = sp.find('**/+GeomNode').node()
for i in reversed(range(gn.getNumGeoms())):
    texAttr = gn.getGeomState(i).getAttrib(TextureAttrib.getClassType())
    if texAttr.getTexture().getFilename().getBasename()=='DEL.jpg':

2 geoms, using the same texture image, but different files :

Sorry but what?

Skirt is the extra border faces as in teedee’s illustration. Its purpose is to preserve the normals at the real border edges. Teedee suggests to render that skirt transparent, while I suggest to remove it at all.

Well, with such simple models, you certainly can’t. But on more detailed models it should be doable. Take a look at the sims. I only looked at the very first sims game but i still know that there were no extra models for e.g. every hair color. The nexk was put into the head model (here the seam) and all faces and haircuts were either separate models or separate textures for the whole head. Same was with the rest of the body, which was divided into up to 2 parts. In Oblivion there were only 2 models per character: head and body. Using key-shapes and attached models for clothes or long hair you could further customize each part.

As your example character doesn’t have any possibilities of seams, I mentioned replacing the whole as that’s the easiest way to terminate all visible normals errors.

Have a nice day.

@ynjh_jo: thanks for the idea.

Look, I know how my models are structured. It is simply impossible. I’ll have to limit the parts of the body which can be edited by the player. Or join the parts and make the modders edit the whole piece every time, which is inconvenient. And I said that I can’t use shapekeys in the other post with a valid reason.
So what are you trying to tell me?

Again, these models are demos I made to demonstrate my problem. I told you this already.