Let's take a longer look at the most successful Dow Jones (DJINDICES: ^DJI) stock of the past year. Insurance giant Travelers (NYSE: TRV) has crushed its Dow peers lately with a 44% gain versus the index's 11% rise. Throw in reinvested dividends along the way, and returns grow to 48% for Travelers and 14% for the Dow.

The stock is a fairly recent addition to the Dow. Travelers and Cisco Systems (NASDAQ: CSCO) were added in the summer of 2009 to replace financial-crash victim Citigroup (NYSE: C) and bankrupt carmaker General Motors (NYSE: GM). How have these changes worked out so far?

GM and Citi have underperformed the Dow since being kicked out. Working your way back from bankruptcy is no mean feat, especially when you're selling the oldest vehicle lineup in the industry. Citigroup doesn't even impress itself anymore, not having even asked the Fed to allow a dividend boost this year. And Cisco hasn't done the blue-chip index any favors so far: The networking expert sold off its consumer product lines and refocused on the data center in a big way, and the payoff of these drastic changes isn't coming quickly.

Travelers muddled along for a couple of years and then flourished in 2012:

TRV Total Return Price Chart

TRV Total Return Price data by YCharts.

Traveler's underwriting policies are stricter than most of its peers', and the company is run by a top-notch management team. That's why Travelers walked away from the Sandy superstorm largely unscathed -- and why the stock is soaring to the skies right now. Run a tight ship long enough, and investors will eventually reward you for it.

Together, Citi and GM would have added 40 points to the Dow since this lineup change. Cisco's 12 points are negligible, but Travelers has contributed 338 points in less than three years. I'd say that's a helpful couple of switches. The Dow would look quite a bit weaker today if the pre-2009 lineup were still in place.

Fool contributor Anders Bylund holds no position in any company mentioned. Check out Anders' bio and holdings or follow him on Twitter and Google+.

The Motley Fool owns shares of Cisco Systems and Citigroup. Motley Fool newsletter services have recommended buying shares of General Motors and Cisco Systems. The Motley Fool has a disclosure policy. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. Try any of our Foolish newsletter services free for 30 days