SCM files use a completely different language, and while you could control things directly with it, you would still need memory hooking methods to complete many of the common tasks you wish to accomplish in LU. That being said, syncing SCM can also cause heavy lag with the more that is in the file, as evident by MTA 0.x's design.
I'm not against synced, custom SCM for those that want to do it, but I wouldn't really recommend anyone go that route, as it would cause more problems than simplify them.