True that having over 100k income and 30k expenses would lead to 50/50, but even the reader case study just posted has a similar 75/25 tax-deferred/taxable ratio. And I agree that I should have minimized dividends and interest in my after tax accounts, but then I'll get socked with capital gains, so I stick with what I've got which is less efficient than a lower yield broad market fund, but also gives me higher FI confidence with the higher yield.
I'd say that's a pretty big leap that a 2MM net worth individual has the same non-discretionary expenses as a 1MM person, and I'd imagine it would take a large portfolio hit to convince them to cut back to what the 1MM guy cuts to. My experience is that people match their lifestyle to their portfolio, and are unwilling to part with the toys and social circles they have become accustomed to, until they have to. The accumulation phase is very different than the draw-down, so I wouldn't apply the experience of saving more as salary increases with how you will treat spending if you keep seeing your balances going up and up as you get older. Market volatility is usually faster, especially on the downside, than lifestyle adjustment, but they do eventually come back in line one way or the other :)