Sometimes I'm struck by the fleeting idea that we pay too much attention to Warren Buffett's thoughts and the stocks that make up Berkshire Hathaway's (NYSE:BRK-A) (NYSE:BRK-B) portfolio. Nevertheless, from my perspective, my Foolish colleague Morgan Housel's recent news that Buffett's been actively buying ConocoPhillips (NYSE:COP) is a big positive.

Oh sure, Buffett may have bought it for reasons that wouldn't hold today, since as of June 30, it was reported that Berkshire owned 59.7 million shares of the Houston-based member of Big Oil. And by Sept. 30, Buffett's Conoco stash had climbed to 84 million shares, making Berkshire the company's largest holder. So, he apparently did a majority of his buying when oil prices were zooming upward, before they topped out above $145 a barrel in July.

But, while Warren and I don't travel in the same circles, I'd be surprised if he were to use a descent to $55 crude -- or even $45 -- as an excuse to lighten his Conoco load now. As you know, he practices exactly what we constantly counsel our Foolish friends to use as their investment mantra: buy and hold. And while the precipitous slide in crude has shocked the pants off energy seers everywhere, there's logic in the notion that, with all sorts of major oil and gas projects being chopped across the globe, any sort of return to economic normality risks leaving crude supplies well short of demand.

So, where Buffett has led the way by gobbling ConocoPhillips shares, it's an ideal time for Fools to follow suit at significantly lower prices. After all, ConocoPhillips' shares are currently trading about 50% lower than their 52-week high.

That being the case, there are actually several ways to approach a Big Oil component of your portfolio. For instance, ConocoPhillips gives you a skinny 5.9 times forward P/E and a 4% yield, while BP's (NYSE:BP) forward P/E is 6.3 times, and its dividend yield is an eye-opening 7.7%.

And then there's industry leader ExxonMobil (NYSE:XOM), whose 10 times forward P/E may tell you something about the company's exalted position among its peers, despite its yield of 2.2% being less than a third of BP's. I also wouldn't rule out Chevron (NYSE:CVX), the second-largest U.S.-based oil company.

The key is for Fools to realize that, despite what we might have thought last spring, energy hasn't shed its cyclicality. As such, it appears that we've been dropped into the middle of a time when buy-and-hold practitioners can build positions in some very solid companies at far less than they'd have paid not too long ago.

More than 4,000 Motley Fool investors have accorded ConocoPhillips a top-of-the-line five-star CAPS rating. Does that include your vote?

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