Well – it happened again last weekend during the Accenture Match Play Championship. Ian Baker Finch, former pro golfer and current color analyst for CBS, was talking about how the ball rolls up the face of an iron, hits the grooves, and thus get spin on a shot.
I hear this a lot on broadcasts, and it drives me nuts. Now, while there is no doubt that these pros turned announcers had a lot of game in their day, I would think that they would do a little more homework before they say things that are simply not 100% true when they are on TV.
Pardon this pun, but national TV is not the place to take a “flyer” at a fact.
It’s a very common misconception is that the grooves on a club face create backspin when, in reality, nothing could be further from the truth.
Sometimes that myth is reinforced when a player sees scuffs on the ball. However, scuffs and abrasions can be caused by the clubface actually striking the ball with the leading edge of a groove, or by an extraordinarily abrasive club face, or because a clubface has hit so many balls that the surface is smooth and the leading edges of the grooves are sharp, but not because the ball rolled up the clubface.
The ball stays on the face of an iron for 4 to 5 ten thousandths of a second, how much time is that for the ball to roll up the face?
In fact, a clubface with no grooves would impart the most backspin possible under perfectly dry conditions. Ralph Maltby, the mind behind Golfworks, actually made and played a set of irons like this and proved his point – when he hit them from tight fairway lies.
Now I am making a distinction between a ball rolling up the clubface and sliding up the clubface. When there is moisture between the ball and the clubface, the ball will slide instead of spin just before it’s launched.
Grooves on a clubface perform the same task as treads on a tire – to channel away surface moisture. Moisture on a clubface acts as a lubricant allowing the ball to slide rather than spin. If slide exceeds spin you end up with a flyer that has very little backspin and very limited directional or distance control. This is a bad thing. By the same token, if spin exceeds slide you have just the opposite. This is a good thing.
Obviously, the deeper and wider the grooves the more moisture can be diverted and the more backspin and control imparted to the shot.
Where does moisture come from (on a dry day)?
Grass.
For shots hit out of the fairway it makes little or no difference what type or size of grooves are involved. The reason is that you are hitting your irons with a descending blow into the ball and making no grass/turf contact until after the ball is gone, therefore you have no moisture to deal with.
However, when hitting from the rough it is practically impossible to eliminate blades of grass from getting between the clubface and ball at impact. Even a single blade of grass will produce moisture/lubricant. What the USGA wanted to do was to limit the amount of moisture diversion produced by grooves so that a player could not generate the same degree of backspin and control out of the rough as they could from the fairway.
In effect, they wanted to penalize a player for hitting into the rough in the first place, after all it is called the rough, not the easy. The groove ruling is simply the USGA’s way of rewarding accurate shot making.
Personally, I think it was unnecessary.
In any event, I just wish the announcers would get it right!
