nice clarification.

btw, the current curation scheme is actually biased towards up-vote IMO. (up-voters always has potential to earn something, while down-voters has zero potential earning while still losing his votes power)

if we were to make the game fairer, we should also reward the down-voters if a post end-up in a negative value in total-accumulated-votes.

but, to do this, we had to first decouple the curation reward from post-reward, 
as suggested here: https://steemit.com/steemit/@ripplerm/proposal-decoupling-curation-rewards-from-post-s