How can I stops background freestyle lines from showing through thin foreground objects when near in zdepth? I have two separate objects both using Freestyle lines. They need to be near each other in zdepth. Being cylindrical, the outside one is both in front of and behind the inner one. The Freestyle lines of the inner one show through the outer one randomly at different places. How can I stops background freestyle lines from showing through thin foreground objects when near in zdepth?

P.S. - I'm using test build 1 of 2.72, but I've had this issue before. Is there a setting somewhere that I can use to eliminate this artifact? Something like.... handling zdepth with higher numeric precision?
The reported problem sounds like another case of a known issue documented in the following page:
https://developer.blender.org/T36350

If that is the case, subdivide big faces of the outer object into smaller faces and see if the visual artifacts are resolved.