Investing is simple.

Investors are complicated.

It's as easy -- or as convoluted -- as that. How else could one explain why most trained money managers, with all of the analytical and ivory tower know-how imaginable, can't muster the smarts to whip a passive stock market index into submission? How else could one explain how legendary fund manager Peter Lynch gained more insight by taking his wife and kids to the mall than by scouring corporate filings?

Successful investing is more about backbone than gray matter. This doesn't rule out the necessity of premium research and due diligence. It does mean that once you find that perfect stock, you hold on for the ride.

That's why you have the market advantage. As long as you're willing to accept your blessing, there is no reason you can't beat Wall Street consistently, lapping the six-figure institutional analysts along the way. That's because you don't have to impress your investors by rearranging your mutual fund holdings every three months. You're not blindsided into trading in and out of positions by executive whispers and false hunches.

As long as you're true to yourself, beating the market is a piece of cake.

My stock, my story
I became a Netflix (NASDAQ:NFLX) subscriber in the fall of 2002. It was a simple decision: I loved movies; I hated the burdensome movie-rental process; I was wooed by a free trial subscription. I had been critical of the company after it went public earlier that spring. Then I tried the service and was blown away. I changed my tune. Isn't it funny how crow can be served up in red envelopes?

Since then, the stock of the DVD-rental specialist has gone on to quadruple in price. It hasn't been a smooth ascent. A few months ago, the stock was wallowing in the single digits due to competitive pricing and the fear that e-tail giant (NASDAQ:AMZN) would enter the market. Weaker hands would have folded at that point. A mutual fund manager concerned over what shareowners would think would have dumped the stock. Halfhearted investors spooked by worrisome headlines would have bailed just as quickly.

I didn't sell. I didn't have to. I believed that the notion of the company's potential demise was sheer lunacy. Its price-slashing rivals were cash-strapped. Amazon would sooner launch its own airline or open up a steel mill before entering the cutthroat movies-by-mail market.

My patience was rewarded. It wasn't because I was smarter than those who cashed out -- I'm not. It wasn't because I'm cuter than those that moved on -- I'm certainly not. It was because I had an unwavering commitment to investing excellence. It sounds bold, but it was really just a matter of having firm convictions in place.

My baby's got backbone
My wife worked as a regional media director for the American Cancer Society in the early 1990s. That included more than a few trips to Tampa, Fla. There, she raved about a local chain called Outback Steakhouse (NYSE:OSI). The company was expanding quickly throughout the state, and all it took was one visit, where I saw folks lining up at the door before its 4 p.m. opening, to get my investing juices percolating. What is this Bloomin' Onion I keep hearing so much about? How can so many people be hungry for dinner at four o'clock in the afternoon?

Those who had the gumption -- and the appetite -- to take a nibble on the Australian-themed casual steakhouse have been richly rewarded. The stock has been a 10-bagger over the past 14 years.

It doesn't take a genius to figure it out. In fact, that can often be a hindrance. A market savant might worry that beef prices will fluctuate or that expansion can prove costly or that most restaurant concepts fail as fads. She passes. A simpleton arrives at 7 p.m. and is handed a pager that will go off in an hour when his table is ready. That's 60 minutes to ponder the obvious. He buys (ideally after putting in a little due diligence to make sure that the company's fundamentals don't betray his grumbling stomach).

Right stock, wrong shoes
I wasn't the only one who spotted Netflix early. David Gardner singled it for the Motley Fool Stock Advisor newsletter subscribers in the spring of 2003. Six months later, the stock had tripled in value.

David's brother, Tom, also kicks in a pick every issue. His very first selection for the newsletter was Moody's (NYSE:MCO), back in April 2002. Yes, that Moody's. The one most of us associate with a horde of bean counters who wag fingers of creditworthiness at debt-packing firms. It certainly didn't seem like a very exciting investment. In fact, you may not have even known that Moody's was a publicly traded company. No matter. The stock has risen by an impressive 135% since Tom dusted it awake.

That's the way it has gone in Stock Advisor. Brother vs. Brother vs. Market. The Gardners have come out comfortably ahead. David's picks have averaged a healthy 55% return. Tom's are up a whopping 67%. The average performance of the S&P 500? A respectable, though vastly inferior 17%.

David and Tom share a commitment to excellence, though their investing styles couldn't be more different. In their real-money portfolios at in the 1990s, David favored industry-altering growth stocks like eBay (NASDAQ:EBAY) and Starbucks (NASDAQ:SBUX). Tom preferred proven blue-chip market leaders like Johnson & Johnson (NYSE:JNJ). These days, Tom opts for a lighter shade of blue, using proven quality gauges of blue-chip fiscal excellence to unearth promising companies when they're much, much smaller.

Since they joined forces in Stock Advisor more than three years ago, it's the best of both worlds for subscribers. 50% peanut butter; 50% chocolate. All spine; all glory. Want to know what all the fuss is about? See for yourself by taking a free 30-day trial. You'll have access to all of David and Tom's market-trouncing picks, including the ones they set their sights on this month.

Longtime Fool contributor Rick Munarriz sometimes fancies grape jelly on his peanut butter cups. He owns shares in Netflix. Along with Netflix and Moody's, Amazon and eBay are also Stock Advisor selections. The Fool has adisclosure policy.