The market has had a fantastic run, but this spike doesn't really matter

But once that's done, timing market peaks and troughs is no longer important in the bigger picture. For example, during the Great Financial Crisis, as a journalist I spent an inordinate amount of time talking to so-called experts about when they thought the stock market would rise or fall. In retrospect I think that was a waste of time.

Suppose you misjudged the market cycle as much as possible, but still decided to become a long-term stock investor—and actually stuck with it despite huge losses. That would mean you would have to buy at the market peak of October 9, 2007. You would have lost most of your money in the spring of 2009, but you would have gained it back, and then some. Here are the returns of the S&P 500 from October 7, 2007 through January 18, according to FactSet:

• Looking at price alone, the index is up 7.1 percent year-over-year, or 207 percent cumulatively.

• With dividends reinvested, the index gained 9.3 percent annually, or 325 percent cumulatively.

I immediately admit that you could have done better by buying and selling at 'the right times'.

That would mean knowing in real time when the market would rise and fall, and no one knows that reliably over long periods of time. You could also have bought and sold the right shares. Just owning Apple, and nothing else, during the same period, and never selling it, would have given you a total return of 3,760 percent. If you did, bravo.

But what are the right stocks or shares to buy over the next fifteen years, and what is the optimal time to buy or sell? Some people will undoubtedly get the answers right.

I'm not even going to try. This market spike means a lot to a lot of people. I view it merely as further confirmation of the wisdom of long-term, low-cost buy-and-hold investing. Let's put this peak behind us and hope for many more to come.