Raytracing + Nonlinear Subdivision Level + Surface with Edges draws too many edges

See attached file which is a sphere meshed with quadratic hex elements.

When showing the element edges (i.e. render as Surface With Edges) and increasing the Nonlinear Subdivision Level from 0 -> 4, the render facets' edges are being drawn when using raytracing.
sphere_hex27.e

Here's the correct behavior when not using raytracing, numbered by the value of Nonlinear Subdivision Level

0. 
1. 
2. 
3. 
4. 

And here is the behavior when using raytracing, numbered by the value of Nonlinear Subdivision Level

0. 
1. 
2. 
3. 
4.