This was originally published on RealMoney. It is being republished as a bonus for TheStreet.com readers.I had a question from a reader last week that intrigued me all weekend. He felt that if his time horizon is 20 years or longer, shouldn't he be averaging into the market right now? I contemplated this over the weekend as I sat poolside with the new George Pelecanos novel (for fans of crime fiction who have not read him, do so now -- he is the master of the art) and enjoying an unusual warm, low-humidity weekend. The answer I came up with is yes, if you have that long a time horizon, I probably would advise that strategy. I have two caveats to this. One, as Warren Buffett once remarked, if you cannot stand a 50% drawdown, do not invest in the stock market. The second caveat is that rolling 10- and 20-year terms that include the start of a recession will have much lower than average stock market returns. History tells us you will have a positive return over a 20-year investment in the stock market. It does not guarantee that it will be a great return or that you will not experience significant drawdowns.