What's best for the business doesn't always drive short-term gains for the stock.When people started complaining about portion sizes at Chipotle Mexican Grill (CMG 2.29%) earlier this year, Wells Fargo analyst Zachary Fedam took matters into his own hands. In the name of scientific discovery, Fedam and his team ordered a whopping 75 identical burrito bowls from various locations of the restaurant chain, meticulously weighing every single one. And what they found was shocking.The difference between Fedam's h ...