I didn't know that, I assumed that it was already enabled by default.
Feb 7 2018
Feb 5 2018
Looks like that's the issue. Alright, I'll make a report then. Thanks.
Alright, but what is the full correct RNA path that I should use to make the "Driver source" directly control "ScaleX"?
It seems like it is another bug, Blender doesn't save the path I specified here using "Add driver from target"