Just wanted to share with you some recent changes that occurred out on the US PGA Tour. As many of you surely know, the players/caddies have the opportunity to purchase course and green books at the events they play. Some will purchase just course books or use ones from previous years (assuming no major course changes). Others will purchase both.
At last years Open Championship, a new player in the green book market started in Europe and was producing much better books for the players. Over time, the pressure for adjustment in our books grew and at this years Barclays, the change occurred.
Here is a picture from an older green book the players could use to help with approach strategy and green reading. Lines represent areas of equal elevation. The closer the lines are together the steeper the slope in the area. Arrows represent the direction of the slope at that location.
You can see large areas where nothing is represented. These are areas that are very subtle in terms of slope change. That doesn't mean no slope change. It means not enough to show change on the scale the book is using. More and more often, these are the places where pins are placed. They do this to try and nullify the use of the books and force players to use past knowledge or their eyes to solve the slope question. These are also areas where slope direction can change in the opposite direction. Subtle double breakers happen here as well.
Now take a look at a newer green book. This image is just half of the green book. The other half looks similar to the one above but I'm sure you can guess there's more detail.
You can clearly see much more detail in the new books. It will be interesting to see if more players start adopting these newer books. At least one of my players has and has seen the biggest improvement from long lags as he can see the flow of the green better with these.
One of the constant issues with using a green book to read your putt is the accuracy of the pin placement on the green relative to the pin sheet and the players ability to locate themselves on the green relative to that position. If either of those are off, green reading answers can be off and trust in the books can diminish.
Hope you enjoyed this little peak into the inner workings at PGA Tour events.