Monte Carlo is an excellent tool. The problem is what you input for the variables. Bob is a person and will alter his behavior given a changing environment. Monte Carlo works in hindsight and in a class room. The probability of event "A" in 2006 may not be equal of "A" 's probability in 2007 or even any of the future years. Finally, why would you look at the probability of Bob living to 120?
Stress Testing Your Portfolio [View article]