Maybe this will be found more easily if it's broken out from the Bernstein FAQ.
The success rates of retirement calculators:
The Retirement Calculator From Hell - Part I
The Retirement Calculator From Hell - Part II
The Retirement Calculator from Hell, Part III, including the quote "Thus, any estimate of long-term financial success greater than about 80% is meaningless."
Retirement Calculator from Hell, Part IV
The Retirement Calculator from Hell, Part V
The success rates of retirement calculators:
The Retirement Calculator From Hell - Part I
The Retirement Calculator From Hell - Part II
The Retirement Calculator from Hell, Part III, including the quote "Thus, any estimate of long-term financial success greater than about 80% is meaningless."
Retirement Calculator from Hell, Part IV
The Retirement Calculator from Hell, Part V