I believe what he’s saying is that stocks, bonds, and cash rarely fall in unison. People shift money out of stocks into bonds if they perceive an impending economic decline, or perhaps into cash if they’re in panic mode or need liquidity. But if, as we saw today, all three are tanking together, it means there’s a wholesale flight out of USD-denominated assets. Money is leaving the country. You see that sort of market movement more commonly in the third world as a country is toppling economically, but it’s unusual to see it here. I’m guessing that’s what’s meant by “balance of payments problem.”

I don’t read much into one day of price action though. Let’s see if a trend emerges.