Yes, I plumb bob. But my methodology is somewhat different.
The object is to stand as near as perpendicular to the ground as possible to get an idea of how much the green breaks. However, since it is not possible to stand perfectly perpindicular, I instead use the methology to try to estimate which way the ball breaks. After correctly surmising this information, it is up to me to estimate how much it breaks. After doing that, I use the plumb bob to pick a spot directly in front of the ball to line up with while placing and addressing the ball.
However, the most important part of the article is the fact that reading other people's putts and chips is the single most valuable piece of information a person can get from a green. I get upset when my partners putt before I am on the green because they are essentially costing me an important advantage that I have earned from being closer to the pin. I can guarantee that my putting average is a lot higher when I am afforded that priceless information than it is when I have to putt first or when my partner's aren't considerate enough to allow me onto the green before they putt.