Abercrombie & Fitch CEO Mike Jeffries is one of my favorites (and let's face it; I like some of their clothes as well), so I tend to keep an eye on the company. Today the stock surged 12% to $65 a share, apparently on impressive sales numbers, attributed by commentators primarily to denim sales.

But the Motley Fool, while generally on target, gets its analysis completely wrong. The writer, who says he owned ANF stock and sold too soon, says the lesson here is to "have faith in your own intelligence and to trust your own stock-selection capabilities." In fact, that is not at all the lesson.

Over the long term, nobody has shown a consistent ability to gauge an individual company and how its performance is reflected in its stock price. Instead, the lesson here is that with individual stocks, sometimes you're just unlucky and get it wrong. Abercrombie specifically has been up and down significantly over the last several years. Everyone seems to agree it's a fundamentally good business (with a penchant for controversy to boot). But whether its stock trades at $64 or $44? That depends on so many uncontrollable factors, far beyond anyone's "intelligence."

Abercrombie could have easily posted the same kinds of numbers at a slightly different time and its stock could have stayed even or even fallen. If the Motley Fool writer had kept his position, that wouldn't have proven his point; it would have been lucky.

Why guess at all? There are fantastic index funds out there to let you ride the market as it evolves overall.

(I don't have any position in ANF. I do, however, own a couple of polos and pairs of gym shorts.)