Thanks for the thoughtful and clear answer. It is telling that when I see something strange in MOI I worry that it is an issue with my computer rather than the software. The model seems to behave perfectly with a tiny plane behind the model, and I am comforted to know that this is just an artifact.

Thanks again for your time.

You might want to make sure that individual objects are not using multiple styles. For instance, select an object and if it shows styles as "varies", then that could also attribute to the darker lines appearing more in the foreground of your display.

Michael T.