Hi rk,
It seems that the Trinity Study has left out a couple of very important parts. That being, before one retires he or she should have enough money set aside to carry themselves through a prolonged bear market. Historically that has been five years. Past that point stocks are an will always be ones best investment and to have one money any place else is a waste of time.
Now I'm well aware that this approach can be unsettling especially if one is a novice or a beginner in stock investing. If one can put aside a minimum of five years money (in mmf or CD's)so that one doesn't have to rely on his or her stock portfolio for support.
This is my take that will work for me. Yours I'm sure is good for you.

Elect5