Dave Pelz, the short game and putting guru, put out a factoid in the late 1970s that hitting a putt so that it would go 17 inches past the hole if it missed is the speed, at the hole, which allows the most putts fall in. Many golfers and teaching professionals believe that. But is it true?
One key to consistent putting is for the ball to approach the hole at the same speed every time. That way, you always know how much break to read since one variable, speed of the putt, is now a constant.
The fastest speed a putt can have and still go in the hole is 4.3 feet per second (fps), rolling over the centerline of the hole. A putt can be going 2.1 fps at the edge of the cup (outside edge of the ball meets the inside edge of the hole) and fall in.
How fast would a putt that grazes the edge of the hole and stops 17 inches past it be traveling when it reaches the hole? Unfortunately, that’s not a question we can give a unique answer to.
Greens have different speeds, meaning the decay rate of the putt differs. They have slope. They have grain. All this means that a putt traveling the same speed can go farther or shorter, depending on those variables. To get the ball to get to the hole at a 17-inch-past speed, it would have to be hit differently almost every time.
Say your target speed is 1.2 fps. A putt going that fast at the hole on an uphill putt will not go as far past the hole as it would if the putt were downhill. How about a bermuda green where you’re putting uphill against the grain versus downhill with the grain? Those two putts will finish at wildly different distances past the hole should they miss, even though they approach the hole at the same speed.
To have all these mentioned putts finish 17 inches past the hole, they all have to be hit at different speeds. That is what you do not want to do.
Pelz did say, and this fact is not paid attention to, that 17 inches is an average, which means it is not a goal. It is a guideline. By the way, I know about the lumpy donut and all that. Modern greenskeeping practices have pretty much eliminated or at least greatly reduced that effect. If it exists, your putt has to be moving very slowly in order for the effect to be noticed.
The biggest problem is that the “17 inches” concept focuses on the wrong thing. Forget about where the ball would go if it missed. Concentrate on where you want the ball to go when it falls in.
Do you want it to hit the bottom of the hole first? Do you want it to bounce off the liner about halfway down? Some other place? Whatever it is, that is what you want to concentrate on, because it is a reflection of the speed at which the ball approaches the hole. You want that speed to be the same, so it hits the liner in the same place.
Drill: Practice this by laying down a club and laying down a coin about a foot in front of it. Now start with three-foot putts and have the ball hit the club just barely. When you can do that consistently, move to four feet and continue. Keep moving back foot by foot, out to about 15 feet.
When you get good at this drill, you have reduced green-reading to one variable, slope. Your line and speed will match up a lot better than before, and you will start making putts you were barely missing, all other things being equal.