The control panel of the graphics card can turn off tessellation even though the benchmark says it's on, taking a screenshot of the score with the stones in it, shows that this is on and working correctly.
They can still use AMD opptimised over-rides or use the slider to reduce the target level slightly below the application set level to artifically increase the framerate without it being glaringly obvious unless you compare it in motion or images with wireframes on - hence why I've not bothered posting results in this thread as I'm not 100% confident some people aren't doing it.