https://finance.yahoo.com/news/4-retirement-spending-rule-back-165856094.html What do others think? I don't think it ever went away.

I assume they use some sort of Monte Carlo Sim to get their numbers. How much of an effect does recent volatility swings have on such a simulation? The 3.2% - 3.8% they quote in the article is a pretty big swing for long-term planning that should be relatively immune to short-term swings

Agreed. I would just be very surprised if recent volatility is enough to change the result, considering we aren't seeing volatility that we've never seen before. Long term planning should be immune to these types of swings.

My view is that the only people who should be using the 4% rule are those who can’t afford a more customized analysis.