Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: The pilot has turned on the fasten seatbelts sign. AMR (NYSE: AMR) shareholders, prepare for a bumpy ride. On Monday, rumors that AMR was flying an express route to bankruptcy drove the shares down 33%. By Tuesday, these rumors began to subside, lofting AMR back up 17%. Today, investors have their value radar turned on, and seem to like what they see: AMR popped another 12%, or close to it, in early Wednesday trading.

So what: The catalyst for this latest bump, I suspect, is word that Wall Street is now on board as well. Yesterday, investment banker Rodman & Renshaw upgraded AMR shares to "outperform," and slapped a $5 price target on the stock. Today, Dahlman "Rose" to the occasion and endorsed rivals Delta (NYSE: DAL), United Continental (NYSE: UAL), Southwest (NYSE: LUV), Spirit (Nasdaq: SAVE), and Alaska (NYSE: ALK) -- and even threw AMR a bone, saying a bankruptcy filing in the near term is "not likely."

Now what: Is Dahlman right? Is Rodman? Perhaps -- but I wouldn't bet on it. On CAPS, we have both of these analysts ranked among the worst investors on Wall Street, and historically twice as likely to be wrong on their stock picks as right. I suppose it's commendable, how they're showing solidarity with unprofitable, debt-laden AMR, arguably one of the worst airlines. But do I think you should actually follow their advice.

In a word: No. 

Disagree? Think AMR will straighten up and fly right? Add it to your Fool Watchlist and see if you're right.