cniv,
Artifact detection is accomplished by rendering into a Direct3D window and scanning the output for problems. It's a visual subjective thing.
You bring up a good point though. I have sent an email to our graphics card guru for a short meeting with him. There may be a way we can improve the test.
There are so many different graphics cards out there and the drivers change so fast it is difficult to objectively define what an error is, some of it will always remain a subjective determination of what is a problem.
I will post back here after I meet with the graphics guy.
-Fred