Removing seam line from surfaces

[rami.evans]

I’ve been trying to make smooth surfaces between two circular curves:

These curves can also be of different diameters. Currently I use the function RuledSurface

but it seems like there is always a seem connecting the two curves. I know this is standard way that Rhino maps surfaces but I was wondering if anyone knows a way to get around this issue? It seems trivial but it is quite an important detail for what Im working on. Meshing will also not work as I need the surface between the two curves to be a single surface and not multiple

[Michael_Pryor (ekimroyrp)]

I know this is standard way that Rhino maps surfaces but I was wondering if anyone knows a way to get around this issue?

Not just Rhino, any software which uses nurbs surfaces. It is not possible to remove that seam. Any untrimmed nurbs surface will always consist of 4 edges, that is how they are constructed.