That's a good page to start with. The option you are talking about isn't there. Feel free to add it (and make it stick , and we'll re-run the benchmark.
Look, I appreciate the work you're doing and all that, but now you're simply pulling my leg.
How about "man radeon"?
I mean, there are people who do not use Ubuntu and I don't see why you're pointing to an outdated Ubuntu community site on the internet when you have the full manual installed together with the driver sitting on your drive.
You do have the point, though, in that the rate of development of open drivers often makes it difficult to follow which xorg options are still valid (and used), which options are new, and what they do. Hopefully things will stabilise as the drivers mature.
EDIT: yes, I understand that this is an Ubuntu benchmark, but still, all these community sites simply parrot things from the radeon man page, which is the same for ALL distributions.
While it's true that the man radeon contains the information you need, man-pages can be a bit daunting. Just check the man xorg.conf. How many Linux users actually understand what it says + how meticulously is it updated?
Some sections even say: "Nobody knows how this works"
EDIT: Oh, and I just want to make clear that I haven't actually read the radeon man page. Didn't realize there was one, so I'll check it out later.