I'm adding this to the thread, even though this isn't strictly about curves, but rather about the 2.5D displacement in general.
I just tried setting up a simple textured lawn thing, and noticed some strange artifacts. Tried to see where it was coming from, and I realised it was coming from the 2.5D displacement. Tried changing to 3D and it's a huge difference.
It's just a simple JPG file, loaded with CoronaBitmap at gamma 1.0 and the bitmap size is bigger than the sample plane, so no repetition there. Displacement is at 1px in both cases.
Help/suggestion?
I think I will consider using 2.5D only in cases where memory is an issue, since the look is significantly worse. :(