Monero avoids this problem, but most of the rest of this proposal has been implemented and running for quite a long time. Its not new, or novel, except in ways that it is not as good.
When Gavin says "I need to see working code", he probably means code he can directly deploy to his test setup within the framework of bitcoin-core. I can relate to this demand and find it reasonable.
Sure, there are quite a few edits that would be needed.
However, it has also been deployed and shown to work over time without pernicious economic effects.