We’ve said it before, and we’ll say it again: Individual investors become their own worst enemies when they choose to play in financial markets instead of investing in them.

But here’s an interesting wrinkle. In one of his recent posts, Wall Street Journal columnist Jason Zweig shared a seemingly contradictory stat on that, in which do-it-yourself investors came out ahead of their advisor-assisted counterparts.

What’s up with that? Are we wrong??

Let’s take a closer look at the case. Zweig’s illustration compares investor experience in two virtually identical Fidelity biotech funds – except one is designed for direct investment and the other caters to investors being served by financial advisors.

You’d expect those who invested directly would engage in ill-advised market-timing and more severely underperform what the fund actually returned, compared to those who were advised to patiently buy and hold. Instead, investors in the advisor-tailored fund did worse in Zweig’s illustration. How come?

The illustration Zweig used may well have been a case of some market-timing investors getting lucky during a specific timeframe. But another culprit to consider may be the “advisors” recommending the advisor-tilted fund.

Zweig describes: “Not all advisers chase performance, but all too many still do. Buying what’s hot and dumping what’s not, they are no less human than their clients.”

In describing what a good advisor should be doing for you, Zweig quotes Dimensional Fund Advisors’ co-CEO Dave Butler: “Advisers [should] provide a human element that gives clients confidence and comfort in not deviating from a plan.”

Zweig elaborates:

“[Y]ou should hire an adviser not for his or her investing prowess, but to help organize your finances, prioritize your goals, minimize your taxes, and navigate the shoals of retirement and estate planning. Done right, those services can make you far richer — and happier — than the pipe dream of investment outperformance is likely to.”

In short, we believe a good advisor should help you avoid, not enable, your “worst enemy” tendencies. Plus, they should be even more disciplined than you are at ignoring any market-timing habits and stock-picking cravings to which they themselves may be vulnerable.

The defense rests.