I have been reading John Jacobs' book 50 Years of Golfing Wisdom recently. In the last chapter, he devotes six pages to a discussion of the 1.62" & 1.68" balls. He is a big believer that the adoption of the 1.68" ball by the R&A led directly to an improvement in the quality of play among the top players in GB&I and the rest of Europe.
He also relates how Roger Wethered wanted the R&A to adopt the larger ball in the 1940's, right after WWII. But Wethered did not want to make any waves and dropped the subject, much to his regret 20 years later.