Subject: Re: Living from Berkshire shares
Is it easy to how this method would differ from selling 4.5% of shares each year in equal quarterly instalments over the same time period?

The main difference is that selling the same percentage of shares each time is WILDLY more variable income.
The "multiple of the smoothed book you own" method has a rolling-four-quarters drawdown of real income of -4% from peak.
For selling a constant percentage of your shares, it's -33% from peak. Though that is aggravated because of the late-1990s price spike, so everything looks lower compared to that for a while.

For a different metric: since 2002, what is the percentage change in rolling-year income compared to two years earlier?
For the "percentage of book owned" method the standard deviation of that number is 4.2%, for the constant percentage of shares owned it's 15.8%.

Jim