I think problem maybe on high pos rewards (100%), community broken trust on poloniex or pumper manipulation or stake holders dump or general bad market or simple bad luck...
In reverse, a multipool paying with SUPER and over few GHZ can buy from market 5-10 btc worth SUPERs daily (if successfully marketted). I can see at bittrex order book, From 2900 to 4290 only 3.8 btc worth buy needed just now. If the multipool miners don't sell daily (mine today sell tomorrow) rewards can be much better for them. Remember we are listed only 1 exchange so when bittrex exchange is handled all done :-)