Reminder, someone at the Fed thought negative rates in 2015 and 2016 were appropriate:
https://marketrealist.imgix.net/uploads/2015/09/Sep-dot-plot...
I'm not saying it was Yellen... But it was Yellen. If they were looking to shock-and-awe this market, talking hike and then going negative would do it.
I have no idea what is going to happen.