Yep. Cool. Yemen busted their printing press for the older notes so they retain their value. 

 Accidental A/B test 

 This is why plebs should also stack a small pile of Benjamins.

With the US default, they could issue a new paper currency. All the old circulating USD will be scarce - valuable. Black market cash. Max privacy. 

 one of the pitfalls of upgrading printing press 😛 

 The world needs more Mises and less Keynes