Last year, PepsiCo (PEP) and its CEO Indra Nooyi were under intense pressure to split up the company. Activist investor Nelson Peltz strongly urged PepsiCo to split up its North American beverage operation from the food business, which houses the Frito-Lay brand. The rationale was that two independently-traded entities could earn a higher valuation than the combined company. But PepsiCo resisted the call to split up, and remained intact. This appears to have been the right call, as PepsiCo stock is up 20% in the past year and sits near an all-time high. Now, another company is making the same decision, although things are turning out much worse. Bob Evans (BOBE) crashed more than 20% on March 4 when it announced it would not split its grocery business and its restaurant business. Investors had long expected Bob Evans to split up, and had bid up the stock price and valuation. Bob Evans was one of the most highly valued restaurant stocks, with a P/E over 40. With the decision to remain intact, Bob Evans shareholders are learning the pain of margin contraction.