Radical, one-time, short-term actions like this aren't lifestyle changes. They're not sustainable, so they don't work in the long term.

If the author said he made sustainable lifestyle changes I'd have some reason to believe he's won his weight battle. If he said he's been getting up an hour early each morning for the past 3 months to walk, or has been learning how to prepare tasty low-calorie meals and has kept that up for the past 3 months, or has taken up cycling and has commuted to the office by bike every day it would be a different story. I know plenty of people who've done these things and successfully kept their weight down indefinitely.

On the other hand, I know plenty of people who've lost weight with short term, unsustainable diets, and who gained every pound of that back.