It used to be common sense that investors couldn't simply realize that it's cold outside, buy shares in a "cold weather play" like Canada Goose and make money, CNBC's Jim Cramer said on Friday.
But in this market, Cramer has watched common-sense investing come back into the fold as a winning strategy.
"Now, I'm not saying that stock-picking's back and index funds and ETFs are dead. No, those days are never coming back," the "Mad Money" host said. "But I am saying that it's possible to pick a group of stocks that are better than average by just keeping your eyes open."
For example, investors who bought shares in oil service company Schlumberger after President Donald Trump announced he would open the country's off-shore sites for oil exploration made money. Investors who bought McDonald's after the company announced a new dollar menu made money.
"For almost two decades, picking stocks with no rigor almost always cost you money. I don't know how long the obvious will keep being profitable," Cramer admitted. "But at least for the moment, simple common sense is actually making people money in this market and that's pretty darned wonderful, if you ask me. But enjoy it while it lasts."