I think the point is that it would work with great certainty if you are able to achieve the requirements (insert long delay/disruption between 2 groups of miners and isolate a merchant node to one side). In fact given a long enough time period the certainty approaches 100%.


Yeah that is the entire point, of the attack.

Anyway, my questions surrounding this attack are:

* Why does the paper call for making an even split between 2 groups of miners, as it's starting point? Wouldn't any division 10%/90% work just as well if you were able to isolate a merchant to the 10%?
* Does this paper highlight anything new? (it seems obvious that comm disruption between groups will cause chain separation and removing disruption will cause one chain to get orphaned).
* For blockchains like Ethereum with short times between blocks I guess the term "delay" is appropriate, but really we are causing a complete comm disruption, for the time under which the attack takes place, between the groups, no?