The announced departure of Don Thompson as McDonald's (MCD) CEO was having an astonishing effect on the restaurant operator's stock -- specifically, giving it the best gain it's had in years.

In recent trading, shares were surging 4.8% to $93.07, a gain of the degree McDonald's, with its $90 billion market cap, rarely sees in a single day. According to FactSet data, the last time it was better was in October 2008.

What it implies is that Wall Street viewed Thompson's management as the main issue holding back the shares and sales growth, both of which were essentially flat the last couple of years. With Steve Easterbrook now set to start as CEO March 1, McDonald's gets another chance to return to the tremendous growth it had between 2003 and 2012. In that span, the stock price went up about 10-fold, and system-wide sales doubled. Then 2012 arrived, a year that included Thompson beginning as CEO, and the days of greatness slowly came to a halt.

All because of Thompson? He'd been with the company more than 20 years, rising through the ranks. That, arguably, suggests it's not entirely plausible he had no idea about keeping the business going in the proper direction. Yet, in his two-and-a-half years as the corporate leader, it was one issue after another, and one attempt at a solution after another. For every offensive move McDonald's made, such as promises to incorporate technology and reshape the menu, it had to make a defensive move, such as dealing with the debate over worker wages or answering a skeptical public's questions about its food quality and supply chain. U.S. sales went into a depression. The financial results for 2014 were poor.

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Stockholders, even getting a dividend they can't do without, had to get more from McDonald's. And Thompson, though the company said he retired, shouldered the responsibility for the fact that they didn't. So in a few weeks, his quarter-century at the Golden Arches will be over.

Difficult days

The very same thing might have happened with any chief from mid-2012 to today. We can't know that, clearly. But, as with quarterbacks in football, CEOs probably get too much blame in bad times and too much credit in good times. That's the world we live in. For Thompson, and McDonald's, the world they live in is changing rapidly. Perhaps it's doing so more rapidly than a 36,000-store base can adapt to.

With McDonald's, there are tremendous forces against the company, forces that go beyond the person in the top office. That doesn't mean Thompson wasn't involved here -- it's a CEO's job to ensure the company gets it right. And during his tenure, competitors from Sonic (SONC) to Habit (HABT) had been looking like fine places to spend money instead as McDonald's once-low prices, a common reason to eat there, climbed. What it does mean is this: Press coverage of "healthier" fast-casual foods has never been greater. Social media has provided multiple platforms for McDonald's detractors. The demand among diners for new flavors and never-ending options has taken over the culinary universe. This is all significant.

Easterbrook, the chief brand officer who has himself spent more than two decades with the company, interrupted by a couple of years away, now will get his chance to show investors and diners that McDonald's can and will be relevant, that the missteps of the recent past were the product of the prior management. Maybe that will prove to be the case. At the least, it'll probably keep activist investors, who've started paying much more attention to the stock, away for a time.

Maybe, however, the problems are because the brand has lost too much credibility or become the most boring of choices over the years. Maybe restaurant remodels, burger-customization options or question-and-answer sessions on McNuggets won't solve anything. Maybe Don Thompson took a difficult job at a very difficult time.

We'll find out if a new CEO is the answer. We'll find out if the original Dollar Menu returns, if breakfast all day and everywhere becomes normal, if wraps will be dropped entirely and so on. It might not matter. Because maybe people are tired of McDonald's, regardless of what is or isn't on the menu, or who is or isn't CEO.

McDonald's as a company isn't in danger of disappearing. It's been an outstanding success as a business, with billions of dollars of profits, and it's weathered storms before. But customer counts are in decline now. It's stopped moving upward, as a stock and as a new-sales generator. If it's the brand that's the problem, it's going to require an incredible CEO to change that.