[donheff]

This paragraph seems to be a short summary:

This method considers failure to mean "having to annuitize your assets before you really hoped to." For most retirees, this is a more comforting threshold to use than financial ruin.

The concept seems to make sense and is easy to implement. You simply put a (moving) floor on your accepted minimum portfolio value that lets you bail out to an annuity when you otherwise risk financial ruin. This requires carefully monitoring annuity costs and availability.

It would seem to work fairly well for someone with enough assets to have a decent breathing space between desired income and "acceptable minimum" income. You have a good chance that market returns will be sufficient to keep you from ever reaching that "annuity funding floor." You can also set your "floor" to leave a chunk of change in the portfolio for bequests or "surprises." For those who start out on the edge - i.e. their SWR matches their acceptable minimum income - it would appear that they are already at the floor and need to annuitize now.