http://www.mrmoneymustache.com/2011/09/15/a-brief-history-of...
http://www.mrmoneymustache.com/2012/06/01/raising-a-family-o...
It's important to keep in mind that his goal was to end his reliance on a full time job for income as quickly as possible, full stop. He did pretty much everything in his power to reach that goal, and it's clear that he's very dedicated.
For anyone who glances at this interview or at his blog and thinks, "I'd like to do that," make sure you read the two posts above first. If your idea of retirement is fuck-you money, a yacht and a summer home in the Hamptons, his advice isn't going to work for you - although his blog provides a good opportunity to gain some perspective on how people not like yourself treat money and what they consider the ideal retirement to be.