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It is about creating 4 sided surfaces so can use the natural flow of the NURBS maths.
Creating some surfaces, then when you have an odd number of surface coming together, trimming to get to a clean 4 sided area to fill.
The example you show is however way excessive.
More like this is better.
You also could use a styled blend or section surfaces in such cases. With this you do not need to create additional cross curves, maybe you can reach G3, and you can modify the shape using the depth and the skew.
Production: NX10.0.3, TC 10.1.4