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." So you might think we'd be the last people to give virtual ink to such "news." And we would be -- if that were all we were doing.

But in "This Just In," we don't simply tell you what the analysts said. We'll also show you whether they know what they're talking about. To help, we've enlisted Motley Fool CAPS, our tool for rating stocks and analysts alike. With CAPS, we'll be tracking the long-term performance of Wall Street's best and brightest -- and its worst and sorriest, too.

And speaking of the worst …
A lot of big bankers have seen their reputations boosted in recent weeks, as they finally got the hang of navigating this here recession of ours, tweaked their stock picks in response, and began improving the accuracy of their predictions. One banker, however, still doesn't seem to "get it." Sadly for Exxon Mobil (NYSE:XOM) investors, it just happens to be the same banker that upgraded their shares yesterday.

Yes, friends, Deutsche Securities grabbed the Tiger by the tail yesterday, starting off the trading week with a big upgrade to "buy" on Exxon Mobil. (It also upgraded ConocoPhillips (NYSE:COP), but only to "hold.")

Deutsche views Exxon as possessing a "defensive positioning to a downcycle that we think will be longer and deeper than the market currently anticipates." The analyst seems particularly impressed by Exxon's ability "to generate cash returns for 2009 of 10%," or "about double the industry average," and predicts: "It will be the lone oil [company] to continue buying back stock." Also helpful on the buy side, Deutsche sees Exxon growing its production volumes by about 5% this year. That's faster than either Chevron (NYSE: CVX) or ConocoPhillips are expected to grow, yet as Deutsche points out, Exxon is "trading only at parity" with these two rivals based on this year's earnings estimates.

Let's go to the tape
Seem like an argument worth listening to? Before you answer, consider Deutsche's record in the oil patch of late. I'm afraid it's a bit hit-or-miss. For example, hit:

 

Deutsche Says:

CAPS Says (out of 5):

Deutsche's Pick Beating S&P By:

Occidental Petroleum

Outperform

****

34 points

XTO Energy  (NYSE:XTO)

Outperform

*****

27 points

... And miss:

 

Deutsche Says:

CAPS Says:

Deutsche's Pick Lagging S&P By:

Nabors Industries (NYSE:NBR)

Outperform

*****

31 points

Frontier Oil

Outperform

*****

12 points

But overall in the broader energy sector, according to CAPS, the analyst has scored well, notching nearly 350 points of market outperformance, even though its accuracy comes in at a less-than-stellar 44%. Over the two-plus years we've been following all of the analyst's recommendations, Deutsche has earned itself a reputation for no better than 48% accuracy on its guesses. This result means that on average, any given Deutsche Bank pick tends to under-perform the market by a small fraction of a percentage point. While not disastrous, it's hardly a record to inspire confidence.

Deutsche Bank: "What we lack in brilliance, we make up in bravado."
As you may recall, fellow broker Bernstein Research encouraged investors to buy "beta energy names" last week, in order to ride a surge in stock price as gas prices "rebound" later this year. (The prediction eerily echoes my own thoughts on Big Oil's Next Bull Run.) Bernstein named Chesapeake Energy (NYSE:CHK) and Transocean (NYSE:RIG) as two of its favorite plays on this theme -- yet Bernstein downgraded Exxon Mobil to "market perform" on valuation concerns.

Perhaps recognizing that its Exxon upgrade would be unfavorably compared to Bernstein's downgrade, Deutsche planted a careful dig at its rival in yesterday's report: "Certainly, we are totally opposed to the 'buy beta' call in oil, even if we believe that prices are reaching a near term bottom on refining downtime."

But the more I look at the stock, the more I agree with Bernstein and less with Deutsche's expertise. Because, after reviewing Exxon's latest financials, I believe the stock is already fairly valued.

Exxon sells for about an 8 P/E, you see, which looks entirely reasonable in light of consensus expectations of 7.4% annual long-term earnings growth. Problem is, those are just "accounting profits." Look a little deeper, and you'll see that it has been five years since Exxon last reported full-year free cash flow that looked as good as its net earnings under GAAP. As I calculate it, Exxon's trading at not quite 10 times enterprise value to free cash flow.

Foolish takeaway
To me, that means Exxon's not much of a bargain relative to its growth prospects. Not a sell, exactly, but not yet a buy either.