Traditional strategies, such as buy and hold, have been around a long time. This can be a risky approach, especially nearing your retirement years because the market will fall and you will lose money.
Depending on your age, will you have enough time to recover?
Modern portfolio theory—this is not “modern,” it came out in the 1950s. The financial times of the 50’s are quite different than today. Where Modern Portfolio Theory may work for the GROWTH of your money, it’s a completely different story when it comes time to retire.