I did a bit of searching this morning on file extensions with the hope of finding some definitive dating. Unfortunately could find nothing as to which came first.

I did find that lots of applications currently use the "SCR" extension. Here are some links and information on which programs use a file extension of SCR. In all my findings I never did find Auto Cad listed as a user.
http://www.research.deakin.edu.au/ja..._world.htm#a19
SCR Screensaver file (Microsoft Windows 9.x) SCR Fax image (Generic) SCR Debug source code (DOS Debug) SCR Screen snapshot file (dBase IV) SCR Screen snapshot file (Procomm Plus) SCR Screen font file (LocoScript)
From
http://filext.com/detaillist.php?extdetail=SCR
It mentions 12 instances where the extension SCR is used. And when discussing the "script" catagory I quote "Various programs use this extension; too many to list individually".
But, it is "only" a problem because Auto Desk makes a global association to the extension. For that they are showing their arrogance.
Just my 2 cents....

and I may be wrong.