Running the lisp with drawing as is. Then undo, scaling by 0.1, running again, I did not see the edge
overlap. But I am not into 3D so perhaps I did not know what to look for. Is the overlap obvious?
As you can see here examining 2 triangles, the first points are identical as are the third & second
points respectively.
Using plain ACAD2000.
Command: list
1 found
3D FACE Layer: "GS-ELEV"
Space: Model space
Handle = AB8
first point, X=539837.13728 Y=293829.99543 Z= 2.82000
second point, X=539828.96328 Y=293844.62043 Z= 2.82000
third point, X=539826.73328 Y=293843.57243 Z= 2.87000
fourth point, X=539826.73328 Y=293843.57243 Z= 2.87000
Command:
Command: list
1 found
3D FACE Layer: "GS-ELEV"
Space: Model space
Handle = AB9
first point, X=539837.13728 Y=293829.99543 Z= 2.82000
second point, X=539826.73328 Y=293843.57243 Z= 2.87000
third point, X=539835.71028 Y=293829.00243 Z= 2.87000
fourth point, X=539835.71028 Y=293829.00243 Z= 2.87000
Oh, it took .99 seconds of the first run & 1.25 sec on the second run.