... theoretically, I could stand side by side with another bump stock owner, both of us holding our little pieces of plastic, and he could go away to prison for a decade while I have a ruling from the DC Circuit that protects me.
That is so weird.
Standard IANAL disclaimer applies.
Not at all when concerning BAFTE. You could have two identical machine guns and if the paperwork weren't in order, one could send you to prison, one is fine.