That, Sir, is very classy. How on earth did you work those out. I'll have to try these when I can figure which way the normals are facing.

Thanks, Mark.  Back in 2012, when I had first began using 3dsmax in school, I was using a interesting plugin called Mathsurf, which was a maxscipt that automatically produced mathematical shapes of all kinds in the Max environment.  This is an example of some objects I produced with it, back in 2012: http://luxxeon.deviantart.com/art/Toroidal-Hangout-321980449

After playing around with that plugin for a while, I began studying the surfaces it produced from the automated algorithms.  The output it produced often consisted of triangle topology, and I wanted to create the same shapes with logical quad surfaces, which are easier to edit and unwrap.

So, the first method illustrated in the video is a very commonly used technique I learned years ago from the Wolfram Mathematica community.  I was searching for a way to model a saddle surface without algorithms, and the people there were extremely helpful.

The second technique, however, is a variation I personally came up with, in a kind of "eureka!" moment, after experimenting with some older subdivision modifiers in 3dsmax.

PS:  It may not matter about the normals in your software, Mark.  The only reason it's an issue in 3dsmax, is because I'm using the "Editable Polygon" object type to create the shapes.  Editable Polygon, unlike the older "Editable Mesh" object types, will not allow you to model single-sided objects with invalid, or non-unified, normal faces.  It intentionally forces you to model proper objects, logically.  However, this is not actually the case in Blender, for example, where you have the freedom to weld points which reside on opposite face normals, without any problems.  As long as you thicken the surface into a solid object in the end, this shouldn't be problematic anyway.  If you were to leave it as a single-sided, non-manifold object, of course, the non-unified normals would become an issue.

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