At The Motley Fool, we poke plenty of fun at Wall Street analysts and their endless cycle of upgrades, downgrades, and "initiating coverage at neutral." Today, we'll show you whether those bigwigs actually know what they're talking about. To help, we've enlisted Motley Fool CAPS to track the long-term performance of Wall Street's best and worst.

And speaking of the worst...
"If at first you don't succeed, fail, fail again." This must be the motto at beleaguered Swiss banker UBS.

Two months ago, I took UBS to task for recommending that investors dive into the steel sector and buy AK Steel (NYSE: AKS) and U.S. Steel (NYSE: X) ahead of earnings. Two months later (last week, to be precise) both AK and U.S. Steel reported earnings. Long story short, the stocks are down 7% and 18%, respectively. (In contrast, free-cash-flow-positive Steel Dynamics (Nasdaq: STLD) managed to hold up fairly well, while my favorite company in the industry, Nucor (NYSE: NUE) actually gained 12%. Which just goes to show you why I believe cash is still king.)

Be that as it may, UBS seems undeterred by its disastrous record to date. To the contrary -- after betting big and losing bigger on AK and U.S. Steel, UBS is doubling down on its industrywide bet. Yesterday, the Swiss megabanker initiated coverage on the world's biggest steelmaker, Arcelor Mittal (NYSE: MT) with a buy rating.

Doubling down on a loser
What has UBS feeling so sure it can pick a winner -- especially after the last time it recommended the stock, UBS underperformed the market by a whopping 60 points on the pick? Perhaps it's the self-published report that Arcelor put out yesterday, which the company coyly disclaimed as "the Q311 EBITDA sell-side analyst consensus" (emphasis added).

According to this report, Arcelor is on track to earn $2.5 billion in Q3 2011, before interest, taxes, depreciation, and amortization are subtracted. If correct, that would work out to about a 10% improvement in gross profit for the company, year over year. It would also suggest the company's doing a whole lot better than its predicted 43% decline in net profit would suggest. And it would help explain why so many analysts on Wall Street are predicting that over the long term, Arcelor will outperform the rest of the steel industry, growing earnings 25% per year over the next five years, while other steelmakers struggle to achieve even 4% annual growth.

Arcelor Mittal: Buy the numbers?
Over the past year, Arcelor stock has underperformed the Dow Jones Industrial Average (INDEX: ^DJI) and the S&P 500 badly (lagging the latter by more than 40 percentage points, for example). But if UBS is right, this weak performance sets up Arcelor for strong outperformance in the years to come.

Consider: At 8.7 times trailing earnings today, and with 25% long-term growth projected for it, Arcelor shares currently sell for a PEG ratio of only 0.37. That's a remarkably cheap price, if true, and helps explain UBS' enthusiasm for the stock. But is it true?

I'm not so sure it is. Or rather, I'm not so sure the "headline" numbers at Arcelor mean what they seem to mean. While Arcelor is incredibly profitable on a GAAP basis, its free cash flow statement shows the company to be lagging badly in the cash-generation business. At the same time as the company was reporting $3.2 billion in net earnings for the past 12 months, Arcelor's cash flow statement showed the company actually burned through $1.8 billion in negative free cash flow.

Foolish takeaway                                               
UBS may be right that Arcelor is on the cusp of recovery, will soon reverse its cash-burning ways, and proceed to deliver barn-burning growth in the years to come as global economies recover. For the time being, however, I'm more comfortable investing in companies that have proven themselves able to generate cash in good times and bad. Companies like Nucor in the steelmaking sector. Or like iron ore miner Cliffs Natural Resources (NYSE: CLF) farther upstream.

Call me old-fashioned, call me a Fool: I think generating cash profits is better business than burning it.

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