When Jim Bridwell wrote, “The Innocent, the Ignorant and the Insecure” in Yosemite for the 1973 edition of Ascent, he had just devised a sub-rating system to the YDS scale that at the time topped out at 5.11.
By adding the suffix letters of a, b, c and d to grades 5.10 and up, he solved the problem of having a broad range of difficulty within a single grade. Until then, some 5.10s and .11s were much easier than others of the same grade.
What Bridwell couldn’t account for were climbers who either didn’t understand the system, or used their egos to downrate established routes. With “The Innocent,” he hoped to add further clarity to the new scale and provide guidance to get everyone more or less rating routes using the same objective criteria—a near impossibility, as we now know.