Invest for the long run - ???

Investing for the long run, as one's only strategy, might be dangerous. See this post. Also:
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You are told that you should invest for the long run. Twenty years for a lot of people is the long run. However, what they do not tell you is that you can see negative real stock market returns over 20 years. It's happened four or five times. So when you're reading in somebody's book that says, "Hey stocks are going to compound at 11 percent a year" or whatever la-la number can be seduced from the data, think twice.
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In secular bear markets, you can have returns for long periods of time from zero to 3 percent, every 15 to 30 years. We're kind of starting one here again. If you went to Standard and Poor's website in March of 2007 and you asked what the earnings were going to be for 2008, their analysts said that earnings would be $92 for 2008. Two months later, at the end of the year in December 2007 – this is four months ago – they were projecting $84. In February, it was $71.20. Today Merrill Lynch estimates that earnings could drop to as low as $45 next year. Notice a trend here?
--- John Muldin, Weekley Eletter, 8/1/08