but goes so far as to predict that there will be a flash crash “a la 1987/1994/1998” in just a few months.

Contrasting his preview of 2018 with the almost concluded 2017, Hartnett sets the sour tone early one, and says that he believes “2018 risk asset catalysts are much less bullish than in 2017” for the simple reason that the bearish positioning going into 2017 has been completely flipped: “positioning now long, not short; profit expectations high, not low; policy close to max stimulus; peak positioning, peak profits, peak policy stimulus means peak asset returns in 2018.” He also goes on to point out that the historical omens are poor:

Having read Hartnett for many years, we can sense an almost tangible undertone of anger and frustration at central banks for making his bearish forecasts for 2 years in a row go up in a puff of smoke. Which probably explains why one of BofA's best strategists has decided to double down, and raise the stakes beyond a simple market crash, and to a flash crash, if only for dramatic impact.