This is an extension, the primary cfg is set in text files with is the right way. "Detect" thing will fail in several cases, although its a good one. It still needs maintenance.
Everything you wrote is non-exclusively correct, lets find a guy who implements it. :P
Which is a completely f*** up expectation of a user to follow and throws back end user computing experience decades into the past.
With SaX2 you were even able to use a windows.inf monitor file to get the correct modeline entries into your xorg if the EDID (which in itself was easily disabled or overridden from a gui) didn't work properly.
Trust me there were a fair number that were PO'd at the discontinuation of SaX2