I haven't thought this through much so I could very well be wrong but it seems those who buy delegation can always be more profitable than someone making money solely on curation because they will try to make as much money as possible on self-voting. 

Those who buy delegation can then always offer to buy delegation at a higher price than what curation can possibly pay back to its owner if the owner doesn't self-vote as much as what the delegation buyers will.

I'm not sure exactly how clear I was. I hope you got my point. 

I think the n^2 reward curve might have solve some of the problem you are underlying with the Steem. Even though it seems totally counter-intuiative.

> If I understand this correctly, n^2 curve incentives people to avoid splitting their votes and splitting their stakes (delegation)?

> It make the largest accounts more powerful than the others in a none linear way. 

> Under such rules, stakes control the reward pool in a none linear proportion changing a very fundamental part of the Steem dynamics.  

> It's pretty hard to try to understand how it effect Steem as a whole but I think I can see why it make sense overall. 

https://steemit.com/blocktrades/@blocktrades/blocktrades-now-offering-steem-power-delegations#@teamsteem/re-dan-re-biophil-re-dan-re-blocktrades-blocktrades-now-offering-steem-power-delegations-20171106t222226834z