That was very interesting about the 1914 UK treasury currency notes. I had never heard that. Pictures are on the the BoE website. As for Greece doing it , I wonder how that would be treated politically. As Galbraith says Greece has international engagements that could be effected . It would be devaluing the euro , on the other hand that is the nature of the beast when it comes to currencies.
The L. Randall Wray proposal was better than a T-bills plan. It neatly sidesteps all legal issues. James Galbraith and Yanis Varoufakis have been very disappointing. They just aren't engaging with the many post Keynesians who have wanted to help.