When the USGA and R&A announced their planned action to restrict the viability -- and therefore, the usage -- of green-reading books, the biggest initial concern was regarding enforcement. How would governing bodies and tournament committees alike enforce the proposed regulations? What would stop a player from using the green books after some kind of spot check? In large amateur and professional events, it's impossible to keep tabs on an entire field's obvious golf activities, much less the indiscernible material under a yardage book cover.
Perhaps realizing the enforcement of their planned regulations could turn the regulations themselves into a farce, the USGA and R&A have moved forward with scaled-back changes to green-reading books.
In the final version of the changes, which will be considered an interpretation of new Rule 4.3, four changes will be made:
- As under the original proposal, images of greens can only scale at 0.375" inch to 5 yards (1:480).
- Green-reading books can be no larger than 4.25" by 7", or what would fit in a pocket.
- Golfers can't make the drawings more detailed and then use magnification devices beyond normal prescription glasses to read them.
- Hand-drawn or hand-written notes will be allowed in the books, provided they're written by the player or their caddie.
What was dropped was a proposed interpretation limiting the minimum slope for green-reading materials and maps to 4 percent (2.29 degrees). The idea was to limit indicators from areas where a hole is most likely to be cut, which is typically less than 3.5 degrees of slope, and require the naked eye to do the work required to read a putt.
Ultimately, the package of changes isn't particularly easy to enforce, but they are reasonable changes in limiting the amount of detail in the books.