Smooth sailing is something that I always seem to take for granted. I'm not sure why. I just grow complacent when the news is neutral to pleasant. You might be that way, too. It's a misleading lull, naturally. Few things ever go as planned, especially on Wall Street. Just when I'm eerily at peace with my portfolio -- splash -- in comes a monster wave and my portfolio capsizes.

Such capsized companies create both chaos and opportunity. Yes, opportunity. It's hectic at first. There are casualties in the pandemonium. Your world has been turned upside down, and you have to single out the Red Buttons and the Pamela Sue Martins who will make it -- and the Gene Hackmans and Shelley Winters who won't.

You don't have to wade through the watery calamity on your own. I've got a trick that I'd like to share with you that should help you get through these tense moments. It may seem outlandish at first, but trust me -- it does work.

What's the trick? I sometimes Poseidon my portfolio on purpose. Like a fire drill or a walkthrough rehearsal, I deliberately turn my stocks upside down just to see if anything falls out of their pockets. The process is easier than you think. And yes, you can -- and should -- do it.

Being Ernest Borgnine
The key to a rock-solid portfolio is to put it through a few simulators. Play out a few "worst-case" scenarios and see how your stocks pan out. I do this all the time with Netflix (NASDAQ:NFLX). I've owned the stock since 2002, and the shares have certainly been battle-tested. The company has gone through a brutal price war, and it's facing the eventual threat of digitally delivered films. It's created a lumpy yet ultimately gratifying stock chart over the years.

Am I concerned over the highs and lows? No, in part because I've played out the potential outcomes long before Blockbuster (NYSE:BBI) got serious about its mail-order business or Comcast (NASDAQ:CMCSA) began offering older films on demand for free.

I didn't have to wait for the reality. Even as Blockbuster's CEO was dismissing the fast-growing Netflix audience as a "niche," it was testing a small service called filmcaddy.com. It was really just a matter of time before the company connected the dots and jumped in before Netflix got too big. In my scenario, I figured that there would come a point at which Blockbuster promoting its online business would cannibalize its offline business and infuriate its franchisees. So no matter how ugly the price war got -- and it did get ugly -- I held firm knowing that it would have to pass.

The digital download challenge will be real. It hasn't been feasible in the past, because cable-based systems have a limited selection, while computer-based services take too long to download, are sometimes awkward to stream, and the PC is not the ideal appliance in front of which to comfortably catch a family or romantic flick.

You do have companies like Best Buy (NYSE:BBY) and Hewlett-Packard (NYSE:HPQ) teaming up to roll out smarter television sets this year, but no proposed digitally delivered service seems to touch on the various special features that come packed in DVDs. They seem to be fighting the linear VHS format that is all but dead without offering the deleted scenes, out-takes, and "making of" features that give discs an extended life beyond the end credits. No major digital rival has been able to duplicate the sense of wonder and gaming behind prioritizing queues, which add a little mystery to the red envelope in the mail.

Do I take the threat of video on demand seriously? You bet, but I've played it through and continue to hold Netflix even through the bleakest of simulations.

Stocks overboard
When you're upside down, blood rushes to your head. That's not a bad place for blood to be, within reason. You also gain an investing advantage from those who prefer to see things while standing on terra firma. That's their loss. It's like running a radio station without analyzing what XM Satellite Radio (NASDAQ:XMSR) means to you. It's like running a jewelry shop ignorant of the potential impact of a company like Blue Nile (NASDAQ:NILE).

Both of those stocks have been recommended to readers of the Motley Fool Rule Breakers newsletter service. The premium stock-picking service has been marketed as a growth stock newsletter. That's rightfully so, but because it specializes in unearthing disruptive technologies before they gain mainstream acceptance, it's more than that. I think any investor would be able to mold the research that is provided there to fit their his or her own investing philosophy. If you're a value investor who loves turnaround situations, you want to stay on top of the faster-growing upstarts that may keep them down for longer than you think. If you're a market bear, digging into these promising disruptors may provide you with shorting ideas of competitors who will feel the pinch. In other words, a growth-stock newsletter isn't just for growth-stock investors.

It's also brain food to make sure you stay alert when you Poseidon your portfolio. The moment you buy into a stock, it's as important to keep tabs on what the established competition is doing -- and where new competition may come from -- as it is to follow the company itself. That will help you play out any disruptions long before they truly do become disruptive.

Few will argue against the notion that the best way to beat the market is to stay ahead of the market. You can do that by coming to the wave before the wave hits you.

Best Buy and Netflix are activeMotley Fool Stock Advisorpicks. Blue Nile and XM Satellite Radio are Rule Breaker selections. You can check out the rest of the RB picks with afree 30-day trialsubscription to be ready to Poseidon your portfolio before summer strikes.

Longtime Fool contributor Rick Munarriz finds that eating, sleeping, and breathing growth stocks will work wonders for your financial health. He does own shares in Netflix.The Fool has a disclosure policy. Rick is also part of theRule Breakersnewsletter research team, seeking out tomorrow's ultimate growth stocks a day early.