What You Are Actually Optimizing

The instinctive objective—“minimize this year’s tax”—is the wrong one and produces the worst outcomes. The correct objective is the present value of lifetime taxes, surcharges, and heirs’ taxes, computed over a 30-to-40-year retirement and a beneficiary who may live another 40 years after that. This dictates three operating rules:

• Paying tax voluntarily in a cheap year, to avoid paying it involuntarily in an expensive year, is rational and almost always correct. The mental block is that the cheap-year tax is visible on a return you write a check for; the expensive-year tax is hidden in higher brackets, IRMAA surcharges, the Social Security tax torpedo, and your child’s marginal rate.
• “Spend taxable first, then pre-tax, then Roth”—the order every retirement calculator defaults to—maximizes the size of the pre-tax balance entering Required Minimum Distributions. Above roughly a $2M pre-tax balance that compounding is the problem, not the solution.
• The decumulation question is rarely whether to draw from a bucket. It is which mix across all three buckets, plus discretionary realizations and conversions, fills the cheap brackets each year without crossing a cliff. The shape of the year is what you control.

The lifetime number can move by hundreds of thousands of dollars on a $3M-to-$10M portfolio purely from choreography, without changing what you invest in. That is the prize.