However I have stated that if we change Satoshi's protocol so that every announced block solution which is not challenged by another block solution within the reasonable propagation window (e.g. 6 seconds), must be based off the previously propagated block solution.
* How do you prove to a syncing node that a given historical block arrived within the 6 second propagation window without having a different protocol for syncing/live nodes?
* Is it possible to differentiate between a syncing/live node in a p2p blockchain without being subject to attack edge cases? (e.g. all proof of stake chains)
What about this attack:
1. Miner A controls a large amount of POW resources and wishes to double spend by creating a bunch of finney blocks
2. They start with the genuine last propagated block
3. Generate a new block on top
4. Nominate the crap out of it with their superior POW resources
5. Fake the time stamps
6. Loop to 3
When they're done, they dump this huge finney chain onto the network which also contains their double spend?