[t]here is no denying that there’s been a shift in market structure over the past few years. Whether it be in the proliferation of free trading platforms, the rise in market share of passive investment strategies, or the ease with which social media can fuel speculative manias further, it does feel like something is different. – FT Alphaville

Yikes, “it’s different this time.”  

Same words to rationalize another bubble,  different rodeo.

OMG!

Timing

I will also tell you my definition of success for a bear market call. It is simply that sooner or later there will come a time when an investor is pleased to have been out of the market. That is to say, he will have saved money by being out, and also have reduced risk or volatility on the round trip. This definition of success absolutely does not include precise timing. (Predicting when a bubble breaks is not about valuation. All prior bubble markets have been extremely overvalued, as is this one. Overvaluation is a necessary but not sufficient condition for their bursting.) Calling the week, month, or quarter of the top is all but impossible. – Jeremy Grantham

In economics, things take longer to happen than you think they will, and then they happen faster than you thought they could. –  Rudiger Dornbusch