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Driver testing: The inexact science behind the controversial method

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MEMPHIS, Tenn. – Xander Schauffele’s frustration still simmered a full week after his dustup with the game’s equipment gatekeepers.

“I just want everybody to be in check. I got put in check. I thought I handled it fine,” he said.

The soft-spoken 25-year-old recently found himself adrift in the complex, taciturn and, some would argue, deeply flawed world of driver testing.

Schauffele became the first player to publicly fail the CT (characteristic time) driver test at the Open Championship – although according to various sources, including Schauffele, there have been others who have failed the test – and his high-profile acknowledgement sparked a conversation that until now had only been addressed in hushed tones and rarely in mixed company.

Last year’s Open marked the first time individual player’s drivers had been selected for testing and even that effort is random with only 30 players chosen. For Schauffele and many others, it’s the first shortcoming in a process that’s riddled with problems.

“It’s not fair just to test 30,” Schauffele said last week at TPC Southwind, a week after his Callaway driver failed the CT test in Northern Ireland. “Knowing how many people failed this time around there’s a certain percentage and if you run that percentage through the entire field there will be others. I’d put a large sum of money that other people would have failed that test as well. Them knowing that and leaving the chance there might be other players in the field with nonconforming drivers while I had to take mine out, which is fine because it failed, I just don’t think that’s right.”

Mathematically, Schauffele’s point is valid. Although the R&A declined to comment on other test results at The Open, if two other players failed, as Schauffele contends, that would be roughly a 7 percent margin, which statistically would equate to 11 players in the 156-man Open Championship field.

But then the only way to prove that math would be if there was individual player driver testing in Tour-related events and that doesn’t happen. Instead, the USGA periodically tests drivers that are pulled from the various equipment vans, not from player’s bags.

This is where it gets complicated.

The Tour defers to the USGA for equipment testing after coming to the conclusion years ago that the circuit didn’t have the expertise or the equipment to accurately administer the test. The USGA, however, proved to be just as reluctant to lift the veil on testing, telling GolfChannel.com in a statement, “we have done testing only at [the Tour’s] request. It’s not something we would do at their events on our own or independent from them.”

The USGA will arrive unannounced onsite to Tour events, “four to eight times” during the season, and based on the Darrell Survey, which tracks equipment usage on Tour, will select various driver heads from the manufacturers' vans based on the different models a particular company has in play. The European Tour has a similar arrangement with the R&A conducting periodic driving testing.

Note, the testing is not done directly to the specific drivers players have in their bags, but rather on a similar model presented by manufactures from their onsite trailers.

There is no driver testing at the PGA Championship and according to the USGA’s managing director of equipment standards John Spitzer, “there currently are no plans to test individual player’s drivers at the U.S. Open.”

Spitzer said the test takes only a few minutes and checks for spring-like effect by using a measurement of characteristic time (CT) device. The test is done by swinging a small steel ball on a pendulum apparatus into the clubface and measuring how many microseconds the ball remains in contact with the clubface.

The allowable limit is 239 microseconds, or 0.000239 seconds, with a tolerance of 18 microseconds. That means a driver can test as high as 257 microseconds and still be deemed conforming.



Schauffele’s driver was over the limit by a fraction of a microsecond (the R&A tested his driver at 258 microseconds) which in practical terms would give the four-time Tour winner virtually no benefit. Callaway Golf president and CEO Chip Brewer released a statement on Monday saying, in part (click here to read full statement), "If anybody deserves blame or criticism for the driver test failure at the Open Championship, it’s us. We provide Xander his equipment. But in all fairness, I’m not sure we did anything wrong. We do everything in our power to design equipment that performs at the limit of USGA/R&A rules but does not exceed it. As long as I am in charge, we will never knowingly produce non-conforming equipment or condone its use, especially in tournament play."

For its part, the USGA deals directly with manufacturers during the testing, which means the Tour doesn’t have any information on possible failures, and according to the USGA the association contacts the equipment company if there is a “model in question.” The test has left the players and the Tour entirely out of the process, which likely contributed to Schauffele’s incredulous reaction to his failed test at Royal Portrush.

It’s also sparked a steady drumbeat from a large portion of players for more testing and greater transparency.

“The more testing the better. It's like anything, drug testing, driver testing. You can test as much as you want, you'll figure out where rules are broken, where rules aren't and who's broken them,” said world No. 1 Brooks Koepka in Memphis. “We see guys are switching drivers almost every other week and you never know. If you can find one after you hit it a few times and it gets hot it might be over [the CT limit], you never know. I think it's a great idea [to test individual player’s drivers].”

Many players agreed with Koepka and there were even some who suggested the Tour could begin testing individual player’s drivers soon, although the practical application of universal testing is sure to be problematic.

“We are always open to enhancing our testing programs and work closely with the R&A and USGA,” said Tyler Dennis, the Tour’s senior vice president of competitions. “We are testing more than we ever have.”

But if more regular and targeted driver testing rings fair to the rank and file, the application of more focused efforts remain a concern for some largely because of the inconsistencies of the testing process. Specifically, different CT testing devices can produce different results and when the threshold is measured in microseconds the margin for error can be far too thin.

“From what I’ve learned, every machine tests differently and depending on how you tighten [the clubhead into the CT testing device] it can give you a different reading depending on how tight or loose it is,” Billy Horschel said. “When you test something all the machines should be the same. They should all be calibrated and give the same reading within a minuscule number.

“When different machines are off by a greater margin then it’s tough to say some equipment is illegal. The equipment the R&A and the USGA test with isn’t too a high enough standard to give an accurate reading on a regular basis.”

Brandt Snedeker has experienced these inconsistencies first hand. Along with Schauffele, Snedeker has been pulled for random testing the last two years at The Open. At Royal Portrush his driver tested just under the conforming limit (256 microseconds). At the beginning of this season, Snedeker had the same driver tested and it was 8 points under the threshold.

“It’s moved 7 points [since the beginning of the year]. I know it’s two different machines, but I don’t think my driver has gotten that much faster this year and I think my driving data would back that up,” said Snedeker, whose driving average has actually dropped nearly 7 yards compared with last season. “Until you give me one driver and I can go to seven different machines and get the same number then what are we doing?”

It’s also curious that a process that’s largely been shrouded in secrecy was performed in a trailer on the Royal Portrush practice range with few of the confidential protocols that you see, for example, in drug testing on the Tour. Schauffele decided to speak with the press about his nonconforming driver because news of his failed test was spreading so quickly among other players and caddies.

“I don’t think the R&A leaked the information,” Schauffele said. “The fact is it was leaked, some way or another, to caddies or other players on the range. During the testing time the door [to the testing trailer] was wide open. I don’t know how it happened. Their intentions weren’t to ruin any player.”

There’s also the issue of how drivers wear down over time and repeated use. According to multiple Tour equipment representatives, who all declined to speak publicly on what is understandably a hot-button issue, a driver that’s tested and found conforming to the CT standard on Tuesday could become nonconforming by Sunday.

“That’s just how it goes. The more you hit drivers through a season,” Schauffele said. “I asked an official and over the span of a season a driver will become illegal based on how hot the manufacturers are putting them out.”

The USGA’s Spitzer confirmed that “the CT of a damaged club (it has a crack or the bulge and roll in the face has flattened) can go up,” and Schauffele said that manufacturers regularly give players drivers that are as close to the limit as possible to maximize the technology. It doesn’t take years of wear and tear, which varies from manufacturer to manufacturer, to push the clubface past the conforming threshold.

To prove the point prior to last week’s Open Championship, Justin Thomas had his driver tested and his manufacturer, Titleist, confirmed it was close enough to the limit that he switched drivers before the year’s final major.

“It's something that over time when you use drivers for a while, they do get hot, they do get a little bit worn in,” Thomas said. “I think that's on the manufacturers to make sure that they are tested and that they are conforming, because it's not fair to the rest of the field if guys are using some and some aren’t.”

It’s all created a deeply flawed and largely misunderstood process that until last week few knew about and even fewer understood. That was until the R&A tested a normally reserved 25-year-old’s driver at Royal Portrush and he refused to remain silent.