Here’s a prime example, courtesy of ZeroHedge, of why the everyday investor should never make “Buy and Hold Forever” stock investments after a major money manager (especially a hedge fund manager) makes an outlandish sales pitch on CNBC.

Guess who, after on September 24 David Tepper almost screamed that he was “balls to the wall long” and EVERYTHING was about to go up on QE2, you were very likely buying shares Bank of America and Citigroup from?

Why, David Tepper, that’s who.

In Tepper’s just released Q3 13F, the Appaloosa fund manager disclosed that in the quarter ended September 30, one week after his pompous, self-serving speech on CNBC served as a reason to pump the market up by almost 2%, he sold 18% of his BofA holdings (his largest holding both at June 30 and September 30), 11% of Citi, 19% of Wells Fargo, 19% of Fifth Third, 19% of Capital One, 75% of his then $157 million Hartford Financial position, and lighten up on pretty much all of his other financial positions.

And congratulations to CNBC for serving as the medium which David Tepper manipulated to his advantage and dump about 20% of his financial stake, which as of June 30 was his biggest, at 56% of total holdings.

That’s right. He used CNBC to give the standard stock broker sales pitch to the whole investing world — uber bullish comments about the Federal Reserve using Quantitative Easing to go long everything but fat guys in banana hammocks and nonworking toilets on dead-in-the-water cruise ship to set off a market rally, backed up by billions of dollars from the Fed’s POMO program — and the market bought it hook, line and sinker. All while liquidating a substantial percentage of his largest holdings by selling into the strength of the rally.

In other words, if you bought stock after this gent’s bullish comments, you had a good chance of buying the same stock he was selling.

So word to the (un)wise: when someone shows up on CNBC telling you they’re uber bullish the market, sector or an individual stock, chances are very good they are already long whatever they’re pitching and will be selling you their shares all while making a tidy profit on your Greater Fool behalf.

If you want to see a 2%, market moving sales pitch for yourself, here’s the original Tepper appearance on CNBC’s Squawk Box:

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