I've noticed some of this correlation lately for sure. I'm just careful with this in my personal trading. Correlation and reverse coorelation come and go. Take gold and the USD, or gold and the SP500. Or, bonds and the SP500, all of which I trade actively. Each of those pairs will reverse coorelate for a time....and then wham, its done and they'll reverse behavior and move together for some time. So, trading these correlations without a view of each chart will frustrate you over time. And, correlation is not a great market signal in my opinion. So, I'm just taking a trader's view. But interesting academically.