I am 7 minutes into the video, and Vlad Zamfir (developer of Casper) has already not underst00d that proof-of-stake has externalities. I mentioned that to jl777 today:
You have no economically viable attack.
Only of we ignore externalities (external economic motivation). The same applies to
the erroneous claim that proof-of-stake is as secure as proof-of-work.
Just because something is possible, that doesnt mean it is certain to happen, especially when it is economically non-viable.
As non-viable as Nxt being controlled by a dictator and Bitshares being controlled by two centralized exchanges.
Also Vlad doesn't seem to fully appreciate that a validator will not be betting against himself if he bets against his historic validation:
To summarize, Proof-of-Stake (including Masternodes of Dash and Casper's consensus-by-betting):
- stakes (or even deposits) aren't permanent because they can be sold (withdrawn), thus historic security is indefensible
Also around the 22 - 23 minute point Vlad makes a reasonable point that having no block reward incentivizes miners to not do game theories that would destroy transaction rate, but he is wrong to assume that is the only possibility. For example a cartel on mining could limit block sizes and thus drive transaction fees higher. Also he is incorrect to imply that proof-of-stake is orthogonal to monetary policy because proof-of-stake can only distribute coins proportionally to stake, which thus the same as no distribution. Vlad has so many myopias, I don't have time to comment on all of them. The myopias are pervasive through the entire interview.
Btw, the interviewing female seems to be quite intelligent. I'm shocked because first female I've seen in crypto currencies and she seems to be a quick thinker.