You've seen people do it. What exactly do they see? Does it work?

They see the BREAK, and YES it works!

HOW TO PLUMB-BOB:

The idea is to stand 4-6 feet behind the ball, then visually line up your zipper, the ball and the hole.
Ex: If the middle of the shaft is two inches to the left of the hole, that's your target. The putt will have, approximately, a two inch break. If the center of the shaft is straight over the hole, there is no break, and so on. 
Hold the putter by the tip of the grip with your thumb and middle finger, allowing the putter to hang freely. This is very important. Some golfers hold the shaft too tight (with 3 or 4 fingers), and influence the hang of the putter. It needs to hang freely to work.

Before starting:

It helps to know which is your dominant eye. Most right handers are right eye dominant, and left handers left eye dominant.

the hole is visible. Where the shaft center points, is where you want to start your putt.
To gain confidence with plumb-bobbing, roll a couple of balls toward the hole until you see the exact break. Now, plumb-bob it. You might have to test your best eye/hand combination. The one that shows you the same break as you just rolled is the eye/hand combination you want to use.

THAT'S IT!! NOW go out and trust that read!     Good luck!

CORRECT

INCORRECT

With your arm stretched out in front of you, close one eye and line up the bottom of the shaft with the ball. Now, follow the shaft up until
person plumb bobbing
holding club correctly
holding club incorrectly
plumb bobbing illustration
plumb bobbing target break

THE LOST ART OF PLUMB-BOBBING

This is the most GOOGLED page on this site. Some say it can't possibly work... I count on it working!

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