Can 21 funds deliver useful global diversification—or mostly camouflage overlap, cost, and complexity? Don opens the Friday Q&A by giving one listener a sharper set of questions to take back to an advisor, including what each fund actually contributes and what would be lost by owning fewer. The questions then move from portfolio architecture to retirement reality. A listener learns why RMDs and Roth conversions should not wag the retirement dog, and another faces a sudden $15,000-a-month...