The problem with patterned parts isn't actually (imho) the lack of normals but the uneven distribution of triangles and the semi flat surfaces you mentioned.
I don't know for sure but I think even if you modeled a similar part using e.g. blender it would still not look smooth purely as the result of the 'weird' (pattern) triangle placement.
Personally I think these kinds of parts are best off using textures. Maybe even move the vector based pattern to the texture (from an all y=0 .dat source), so software can generate a texture of any quality merging the best of two worlds.
I don't know for sure but I think even if you modeled a similar part using e.g. blender it would still not look smooth purely as the result of the 'weird' (pattern) triangle placement.
Personally I think these kinds of parts are best off using textures. Maybe even move the vector based pattern to the texture (from an all y=0 .dat source), so software can generate a texture of any quality merging the best of two worlds.