Pebble Beach, Calif. - Dick Rugge, the USGA's senior technical director, said Thursday that the new rule restricting the size and shape of grooves appears to be working as expected.
Speaking with a group of fans at an American Express tent at the 2010 U.S. Open, Rugge cautioned that it was still "very early" to proclaim the rule change a success, noting that the USGA has only five months of results to compare with data gathered over the previous 20 years. American Express is a USGA corporate partner.
Rugge said that the introduction of square grooves in irons in the late 1980s had changed the game and taken away some of the premium on driving accuracy, especially on the PGA Tour. "It was too easy to hit out of rough onto the greens" with deep square grooves, he said.
"One of the key skill parameters in golf is driving accuracy," Rugge said. "And it was a very important predictor of scoring and winning in the 1980s. But that parameter dropped significantly between 1990 and 2003, to the point where there has been zero correlation between accuracy and winning during the last few years.
"We want to return to the parameters of the '80s and put more of a premium on accuracy. So far this year that has been happening."
The change came after years of analysis by Rugge and his team of engineers and Ph.Ds at the USGA's Research and Test Center in Far Hills, N.J.
"Arnold Palmer told me in a meeting several years ago that the biggest mistake the USGA ever made was letting square grooves in the game," Rugge said. "Who was I to argue with Arnold Palmer, so I told him we'd look into it."
Rugge said he worked closely with club manufacturers for several years to determine appropriate parameters for the new rule. "I'm not saying they loved it," he said. "Importantly they understood what we were doing and worked with us."
The new rule does not ban square grooves but mandates smaller grooves with rounder edges. It went into effect in professional tournaments this year, but is being phased in for other golfers. Amateurs who compete at the highest level, such as in USGA championships, will be required to conform with the rule by 2014 while the average golfer will not be affected until 2024.
Rugge said there is no doubt that advances in equipment, including balls, have helped the average golfer. He pointed out that the average male golfer's handicap index was 16.5 in 1994, but had improved to 14.3 this year. In the same time frame, the average woman's handicap improved from 30 to 27.
Larry Tarleton is a member of the USGA's Communications Committee.