I should make it clearer, the witnesses are deciding currently that STEEM is worth 6 SBD for every 1 STEEM. This means Steemit is giving you 1 STEEM for every 6 SBD you earn on the portion they redeem. Fair isn't it.
A lot of the calculations are hedged on the belief that 1 SBD = 1 Dollar, but with current market prices it isn't true. The feed dynamics are not working according to free market beliefs