I do have to add though that STEEM/SBD does still follow the price of bitcoin versus USD, but that's also largely due to the fact that the primary pairs on bittrex and poloniex are STM/BTC, SBD/BTC, so they've been holding their ground in BTC, they're still going up and down with BitCoin's value in USD.
For example, I'm seeing BTC down 1600 this morning, and here's what STEEM/USD looks like (based on polo's STM/BTC pair):
In general, steem has its own heartbeat different than most alt coins, you must give it that...