Be Careful, Be Very Careful of Optimism on First Solar

NEW YORK (TheStreet) -- First Solar (FSLR) is back!

The beleaguered U.S. solar company is proving skeptics wrong, according to Marketwatch, and is ready to beat its Chinese rivals, according to Bloomberg.

The only problem with its so-called turnaround and competitiveness with Chinese rivals is, well, nothing has changed. Remember, First Solar was one of the stock market's most spectacular crashes in history. What follows are arguments against the bull case for First Solar.

First Solar shares are up 60% in the past three months!

To heck with you skeptics.

Of course, First Solar's shares are down 75% in the past year! Folks, this is what you call a junk rally in a massively destroyed -- and shorted -- stock. You see it occasionally in shares of Green Mountain Coffee Roasters (GMCR) and coal stocks like Alpha Natural Resources (ANR) . Such companies have good days because they've had so many bad days.

As of the end of August, short interest in First Solar was still near-50% of float (33.7% of shares outstanding), and that is going to affect trading when the company announces a new project award here and there. Let's not also forget that with all the major equity indices testing multi-year (or even pre-financial crisis) highs recently, it's a time when investors turn to "junk" stocks because everything else is pushing the limits of reasonable valuation.

Even when First Solar was at the lowest of lows of $11.43, there was a case to be made that the company was transforming itself into an engineering, procurement and construction company of large-scale solar utility projects around the world. As I wrote long, long ago in a solar galaxy far, far away from today, if it works, slap a utility-industry-like multiple on First Solar shares and you've got a stock worth somewhere between $20 and $40. So I wouldn't get too excited about a rally all the way to $22.