Are investors overreacting to the news of the CEO's departure, or was a correction in the stock price warranted given its high valuation?Chipotle Mexican Grill (CMG 0.81%) has been a top growth stock in the restaurant industry for years. Its rapid growth has made it a top investment to own, with shares rising by 300% over the course of the past decade.Recently, however, the company lost its CEO, Brian Niccol, to Starbucks. Even the excitement surrounding Chipotle's 50-for-1 stock split hasn't been enough to ...