Xorg.conf that's soo(append many more ooo here) yesterday.
I never had to edit my Xorg.conf in the last 1.5h years because was empty.
Now all the relevant stuff has been moved to /etc/X11/xorg.conf.d/, and having one single configfile is deprecated.
I have one file in there to change the keyboard layout.
And yes I'm running dualscreen an ati radeon.
So I don't know what's your problem.
This. This is my problem. Once upon a time, about 15 years ago, I could make X jump through the right hoops by editing the config files, although I'm pretty sure it was XF86Config back then. Dot clocks and all that. xorg.conf was kinda sorta like that, so I could deal, and chipset support got good enough you no longer had to go in and figure out which rev of the S3 or whatever you had.
Then some idiot decided to make it "better" by changing everything, instantly obsoleting all that knowledge, and not actually improving anything, and failing to adequately document the new system.
It's great that the new system "just works" for you. But I'm damned sure it doesn't "just work" for quite a few people. Your post basically says, "I don't have a problem, so you shouldn't have a problem," which is pretty much like saying, "I had a three-course meal last night. I don't see why you should be hungry!"