Yep, that does appear to be the case. @dale
https://developer.rhino3d.com/api/RhinoCommon/html/T_Rhino_Geometry_CurveOrientation.htm
Maybe i am wrong on this matter, but I think this was the case in Rhino 5 and got fixed in Rhino 6 already?
No, I tested it, it’s not fixed… that is to say the documentation does not match the function returns.
Yes, you are right. The return value got swapped from Rhino 5 to 6 but apperently the return values got swapped in the Rhino 6 documentation as well. Now the return value fits with the Rhino 5 documentation.