Hello Stephan
I conceived a method for how a digital PoS currency could possibly have a 10 second average transaction time, if it had a block time of 1 minute. I wrote about this on r/BlackCoin before you published your whitepaper. Adam Kryskow of the BlackCoin Foundation has since told me that my method is essentially the same is your. From what I understand of yours, that is the case. However, I envisioned a much simpler and mush less powerful implementation than your sub-second proposal.
Right. My main theme is to implement Nick Szabo's idea about agents with non-forgable logs, what an academic paper I cite calls tamper-evident logs. The proof-of-stake is used mainly to deter Sybil attacks, as there is only a certain amount of stake in the post-fork bitcoins that will be thus qualified for dividends.
The single nomadic mint is permitted by the notion of cooperating agents that do not trust the mint, but rather allow it to timestamp the incoming new transactions from clients. The peers verify the mint operations by replaying the operations themselves as they each assemble the blockchain replicant locally in canonical timestamp order. The single mint in turn permits a non-forking blockchain and definite transaction acknowledgment back to the client with sub second response time.