Display Conduit Geometry Goes Dotted when Control Points Turned On

I have a RhinoCommon plugin in c# that draws some persistent curves. The plugin is built for both Rhino 5 and Rhino 6 (using shared projects in VS which is kind of interesting but unrelated). In Rhino 5 only, when I turn on the control points for any surface, the solid lines I have drawn (using a display conduit) turn dotted and are very hard to see. Rhino 6 does not do this.

Any thought on what might be causing this and how to fix it?