This has been this way forever, but it always bothers me. Why don’t I get options for continuity when my input curve is a 3-point degree 2 curve? It should at least be possible to have tangency to one of the rails, right? I can apply tangency after I run sweep2 without any rebuild, so I know it’s possible.

no options.3dm (54.2 KB)The curve in your example is rational. The curve is rational. The continuity options only work with non-rational curves. Probably the most common occurence of degree 2 curves in Rhino is as rational degree 2 curves to exactly represent circles, arcs, ellipses and other conic curves.