Warsh's first press conference as Fed Chair is likely to be the most important event risk of the meeting.

With The Fed leaving rates unchanged as practically 100% expected (with no dissents), and a very hawkish signal sent from the 'Dots', the question on everyone's lips is simple: "What Will Warsh Do?" (WWWD?)

A dovish Warsh would be the surprise with the market more than fully-pricing-in one rate-hike this year:

From a regime-change perspective, he is also expected to drop forward guidance on future Fed actions, even going so far as dropping the 'Dots' (and has been vocal about the size of the Fed balance sheet), which could raise uncertainty and this push bond vol higher.

Amid all of this Bloomberg's Michael Ball says that, from a trading perspective, the curve-flattening case is straightforward: firm growth and sticky inflation keep Fed hiking risks alive at the front end, while fading energy-tail risks and a more independent-looking Warsh should reduce term premium farther out.

A centrist, inflation-conscious Warsh is enough to flatten the curve further.

Reporters will be asking about: a 'missing dot', a drastically more hawkish 'dots', a dramatically-shortened statement, and a clear hawkish bias (seemingly more focus on the inflation side of the maNdate more than employment).

Watch Kevin Warsh's first press conference live here (due to start at 1430ET):