Is Groove Rule Finally having an Effect?

[Moecat]

http://www.golfdigest.com/golf-equipment/blogs/hotlist365/2012/06/is-groove-rule-finally-having.html

 

As we all wait for the weekend and whether Sweden's test of a shorter golf ball will either fuel or douse the flickering flame of a ball rollback, I am reminded of the last golf equipment standards speculation kerfuffle of this generation: the grooves debate.

 

The grooves debate, which led to the rule change that was designed to reduce the effectiveness of grooves to impart spin to the ball for shots out of the rough (among other things), got its public start when USGA Senior Technical Director Dick Rugge studied the correlation between various golf statistical skills (driving distance, putting, greens in regulation, driving accuracy) and rank on the money list. Rugge produced some charts based on that research that showed most notably how the correlation coefficient between driving accuracy and money rank had deteriorated to the point where it was less than zero by 2004. Throughout the 1980s and early 1990s, it was around 0.5, which is a pretty significant correlation as these things go. (For you non-statistics geeks, a correlation coefficient ranges from 1 to -1. Example: A correlation of "1" means the player ranked first in driving accuracy also was ranked first on the money list, and so on down the line. A correlation of -1 means the person ranked last in driving accuracy is ranked first on the money list. A correlation of "0" means there's no statistical link between driving accuracy and money rank.)

 

The groove rule eventually developed from there, and since its implementation on the PGA Tour in the 2010, the question has been would the correlation between driving accuracy and money rank return to the halcyon days of the 1980s. Rugge has made the case that it would take three years before anyone should start seeing how the rule might be changing play at the elite level.

 

We're six months away from the three-year mark, and while there has been little indication in the first two years that the correlation between driving accuracy and money rank has changed, there is a curious movement in the numbers this year.

 

By my calculations, through the first five months the correlation coefficient is 0.38. If maintained through the end of the year, it would be the highest that number has been in 20 years. For the last three years that number, by my figuring, has hovered around 0 (again meaning there is no relationship between a year of driving accurately and a year of consistently winning a lot of money). It's about five times the average of what it was from 2001 to 2006.

 

Could the change in grooves be dictating who is successful on tour? So far this year 13 of the wins have come from players who rank in the top 50 in driving accuracy. Only 4 winners this year rank outside the top 100.

 

Half a year does not a trend make, but it bears watching.

 

--Mike Stachura

[revkev]

I think the key there is ------- half the year does not make a trend.

 

Let's see when the results are in - Sight unseen I'd say the biggest prize, the Masters, went to one of those 4 outside the top 100. While I don't know where Matt Kutcher ranks in terms of accuracy he was hitting the ball ridiculously long the week of the Players.

 

It does bear watching but I remain in the camp that says, "Can you spell over reaction", in regards to the groove thing. There was a far easier way to increase the importance of driving accuracy - increase the penalty for wild drives by growing the rough, putting the tees in position where wild long drives end up in a hazzard, OB or in the trees or, wait for it, just live with the fact that at the highest level the game of golf has changed. No big deal - other sports have changed to - we still watch them.

[RoverRick]

This was and is stupid rule and an example of someone using statistics to justify a flawed argument.

[Shambles]

I'm ambivalent about these things these days.

 

I didn't like the groove rule because it mandated a change of equipment. However I have not liked the aggressive grooves because they eat up and damage the ball too easily.

 

Thankfully, I am too old to ever reach the point wherein I have to change, and certainly far from good enough to need to change for the sake of a few tournaments. With that said, I'll probably pick up a couple of CC clubs one of these days when the mood strikes to get an idea of what they are pushing.

 

Golfers, on the whole, have learned to strike better and hit farther these days. I think the needed accuracy is still lacking and also the needed ball control, but generally, golfers do look more impressive than in the past. Of course, I'm speaking of the general run of amateurs and speaking in anecdotal terms. There is just no way for me to be definitive and so must just observe. There are more good players these days than in the past. I doubt the changed grooves will have enough effect but cannot really say until I have a set or two to try out.

 

 

Shambles

[JMiller]

I am on the other side and agree with the rule but I also am not sure it was the best move for all golfers, time will tell top AMs switch in 2014 and the general public switches in 2024 I think. If you are a top AM you might as well start playing them now and get used to it by time 2014 rolls around you should be adjusted. The reason that I agree with the change is simple research on spin numbers not statistics between the driving accuracy and money list, there was a bit more that went into it then just that.

 

I highly recommend reading the USGA published documentation on spin generation. Here is the link to their Equipment Research http://www.usga.org/Content.aspx?id=24246. More Specifically I recommend reading this one out of all of them --> http://www.usga.org/workarea/linkit.aspx?linkidentifier=id&itemid=10576

 

On 5 iron shots and 8 iron shots (look on pages 4 and 5 for the chart on the 2nd link) you got MORE spin in medium rough on the old grooves then you did on the fairway. That I see as a big problem, that is the underlying problem as to why driving accuracy didn't mean anything anymore and would give the guy hitting 350 a massive advantage. even when they were in rough. "bomb and gouge" I think was born from that whole idea the rough was not a penalty to play from it was truly an advantage.

 

Personally I think if you hit a fairway you should be rewarded with a more controllable shot. If you hit the rough you have to work for the good shot. old-grooves it didn't matter where you were and heck most time a good lie in the rough was a better result in then a good lie in the fairway.

[Tyk]

If I understand what you are saying Moecat, you are saying that so far, in 2 of the 3 years since the groove change, there has been no difference in the driving accuracy coefficient, and in the first 1/2 of the 3rd year there has been a substantial difference. It sounds to me like it is really valid to question if it is the groove change that is making the difference this year. One would think that if the grooves were the determining factor, then in the first years after the change the difference would be the MOST pronounced as the players learn to adapt to the change, not after they have been playing them for 3 years. I would say based on the numbers that the premise of the grooves being the factor is flawed.

 

Some things that would be interesting to know: were there other stretches of time within the 3 year sample that the driving coefficient was up or down? Is there any consistency to those numbers? Could it be that certain types of courses with certain types of grass, both fairway and rough, impact the statistics moreso than others? Could perhaps the Tour's West Coast swing impact the stats more or less than the Florida courses and we can expect to see the numbers level out to zero through the 2nd half of the year? What are the changes in overall driving statistics? Meaning overall are players driving the ball further? For years we've heard about the "new" bomb and gouge style of play, which was the idea that some guys are just substantially longer than others and use their length to overpower a course. If the rest of the field is catching up to the bombers, then it is reasonable to expect that the advantage of the bombers will be reduced, and the most accurate of the now overall longer field will be more often rewarded.

 

I think the numbers themselves invite investigation and don't necessarily show that the groove change is what is driving the statistical change.