Dude- very good post (and blog). There IS one exception in the Federal statutes on a non-FFL transferring a firearm across a state line- and it is used rarely. That is inheritance.
It is lawful to transfer an inherited firearm that has been left to someone, as long as it is not unlawful for the recipient to possess that gun in their home state. This is at the start of 18 USC 922, and gets missed frequently.
18 US Code Section 922.
It shall be unlawful.....
5) for any person (other than a licensed importer, licensed manufacturer, licensed dealer, or licensed collector) to transfer, sell, trade, give, transport, or deliver any firearm to any person (other than a licensed importer, licensed manufacturer, licensed dealer, or licensed collector) who the transferor knows or has reasonable cause to believe does not reside in (or if the person is a corporation or other business entity, does not maintain a place of business in) the State in which the transferor resides; except that this paragraph shall not apply to
(A) the transfer, transportation, or delivery of a firearm made to carry out a bequest of a firearm to, or an acquisition by intestate succession of a firearm by, a person who is permitted to acquire or possess a firearm under the laws of the State of his residence
Translation- My father dies without a will. I am his only heir. I live in a different state. I can go pick up my dad's shotgun.
My Dad dies. His will leaves me his shotgun. The executor of the estate can ship it directly to me, without sending it to a FFL.
What we have here is... failure- to communicate.