Over the years, when the market has gotten really wacky, tense and emotional, I have tended to always check in with the king of momentum investing: William O’Neil — or at least his organization, which includes Investors Business Daily.

I’ve actually never talked to O’Neil, but I’ve often been surprised to hear they were long gone from (or certainly cautious on) some of the biggest momentum names when the market — or at least a cluster of names — has appeared to have gotten out of control.