There is nothing that will put an end to a good round like three putting. In fact poor lag putting costs more strokes per round than poor drives or iron shots. Every week on tour the person who wins usually has the fewest, or close to, three putts for the tournament. Unfortunately most golfers do not spend much time practicing lag putting. It is not much fun to sit on a practice green and hit thirty foot putts for hours. It is much more entertaining to swing away with a driver on the range or play a quick nine.
When it comes to putting drills it often pays to become creative. Lag putting is as much feel as it is technique, but there is not anything else in life that really prepares us or teaches the touch and feel used in putting. It is very easy to have that last second thought of leaving it short followed quickly by an extra burst of hand speed and a putt that flies by the hole like an Indy car. This happens to everyone but can be stopped if a little creative practice is put in place.
While most people struggle with a putter in their hands it does not mean they completely lack the ability to leave short second putts. To help yourself with the feel of controlling distance simply throw the ball. On the practice green stand as if you are lining up a putt, only without a putter in your hands. Hold the ball in your hand, make a simulated stroke and release the ball on your way through. It is a more natural feel for us to throw the ball rather than hit it and the amount of force and speed needed is remarkably similar. Do this several times then start hitting putts again while thinking about tossing the ball to the hole with a nice smooth tempo. I have even seen very good golfers practice by tossing change in a jar from five feet to improve feel.
The bottom line is great putters have the ability to relate the amount of force or speed needed to get the ball to stop near the hole. This is something that comes with practice but often times different visual cues are needed the break through. So try throwing the ball to the hole and you may have a little less stress on the next putt.