Surface edge curves display through objects

Is there any way to fix this? Is it a Rhino thing or graphics driver?

You could try ‘TestZBiasFactor’ which ‘might’ help.

Thanks!

Is this setting per file?

Yes, it is. You could add it the startup commands with a value that works for you but in theory newer versions of Rhino shouldn’t need you to use this at all. That is why the command never made it to a regular command.

in theory newer versions of Rhino shouldn’t need you to use this at all.

this is happening pretty regularly for me… what exactly is that theory based on?

You should read the echos of commands on the command line. For this command it says:

If you constantly use the “TestZBiasFactor” command to fix display artifacts, please send a sample model to McNeel technical support so we can fix Rhino and get rid of this test obscure command.
Are you sending in your sample models?