ColdFusion Scopes: Part Deux - "Mutually Exclusive" LOCAL and ARGUMENTS

While playing with LOCAL and ARGUMENTS scopes and the scope order bug, I also came across a behavior that I didn't really know about - LOCAL and ARGUMENTS scopes in a CF function are supposed to be "mutually exclusive". Maybe I misunderstand what that phrase means.

https://gist.github.com/shawnoden/ef494ef92ccd3821a189 http://help.adobe.com/en_US/ColdFusion/10.0/Developing/WSc3ff6d0ea77859461172e0811cbec09af4-7ff1.html http://help.adobe.com/en_US/ColdFusion/10.0/Developing/WSc3ff6d0ea77859461172e0811cbec0a66e-7fe2.html http://help.adobe.com/en_US/ColdFusion/10.0/Developing/WSc3ff6d0ea77859461172e0811cbec09af4-7fdf.html