Why the drop in the stock could be an overreaction.Shares of Chipotle Mexican Grill (CMG 5.06%) pulled back following its third-quarter earnings report, reversing the recent momentum the stock had seen this autumn. The drop in price stemmed from its sales coming up just short of analysts' expectations.The popular Mexican restaurant chain is currently in the midst of a transitional period after its CEO left to take the helm of Starbucks. The company is also dealing with the fallout of having to retrain about ...