If 80% of delegates act differently from the wishes of stake holders, they can be voted out. So, I think the only major worry would be someone gaining 51% of the money supply and attacking. Even then, it would be a stupid waste of money, as you are killing something you own a majority in and spent a lot on to gain that stake.
If 60% of stakeholders decide something should be done differently.. Then that is there choice, no? The ones that don't agree can sell their stake and start a new chain on their own. That makes sense to me because Bitshares looks at cryptocurrencies as a business. If you own 51% of a business, you should be able to do as you please. It is like how a democracy would work or business would work in the real world.
Exactly, DPoS works like a representative democracy. Bitcoin doesn't but is designed anarchistic in nature where a majority of the community nodes, miners, or developers cannot force any user or miner with new changes they disagree with.
There is a reason I used the figures of 60% DPoS stakeholders and 80% of the delegates. Ever notice how in representative democracies, politicians will campaign on one platform and than have no obligation to fulfill their promises once elected. Nowadays you can almost guarantee they won't do what they promised and often the opposite. What guarantees do stakeholders have that their delegates will fulfill their promises and remain true in character? You say it would be counter-intuitive for any delegate to do anything to harm his investment but I just gave one example where a majority of delegates could decide upon something harmful that they would assume is beneficial: blacklisting.
With Bitcoin you always have a choice , down to the individual, and the miners and developers are held in check by a revolt(hard fork) that could happen at any moment something controversial is proposed. Not so with DPoS , because by design all users whether they vote or not are under the "social contract" of going along with the majority.
Ok, well minus my misconceptions on how a Bitcoin 51% attack would go down it seems we are almost on the same page.
There are no guarantees that delegates will act in the best interest of stakeholders, or do as they campaigned that they will. However, they do have something at stake that is incentive to not go against a majority of the stakeholders will.. their job which they are being paid for. They could be bribed or collude to act in some way that is against the stakeholder's wishes, but any action that goes against a majority of stakeholders would be short lived as they can be voted out.
If my understanding is now correct from your insights, it would be much like a 51% attack on a PoW coin would work, they could only double spend one or a few transactions before being caught and voted out. Same with blacklisting or withholding transactions. So, IMO colluding delegates and/or hacked delegates would not be a "coin killer", as they can be voted out with minimal damage done.
I think delegate collusion is highly unlikely for the same reasons some people think a 51% from a government entity is unlikely, people would find out about it. If the colluding delegates contact only one delegate that is not on board with what they are doing, it is very likely he alerts the community to the plan and the delegates are voted out before they can even do anything. Needing 51 delegates I think makes this highly unlikely for someone to be so lucky to contact the 51 delegates that would be on board with their plan and not have 1 that isn't.