i don't think people are understanding the point I'm trying to make. I don't care how fast a club wants their greens. They can do it however they wish. BUT if they have the greens at say 10 when they rate the course and then they set the greens at 12 or 13 normally then they have a flawed course rating. Greens, bunkers, tees, trees , doglegs are all stationary but green speeds can do more to determine difficulty than any one element and too fast can make a rating go out the window...
Our club was recently re-rated and the raters purportedly suggested they would assign one rating if the green speeds were consistently above 10 and another if they were not. The difference was pretty significant.
There would be a difference, but less than one shot on the course rating if you increase the stimp from 9' to 12'.
I looked at three recent ratings as a sample and increasing the stimp reading would change the CR/Slope:
6645 yard course
at 9' - 72.6/133
at 10 - 72.8/134
at 11 - 73.0/135
at 12 - 73.3/135
6531 yard course
at 9' - 71.7/125
at 10 - 71.9/126
at 11 - 72.2/128
at 12 - 72.5/128
6705 yard course
at 9' - 72.4/131
at 10 - 72.6/133
at 11 - 72.8/134
at 12 - 73.1/134
On moderately and highly contoured greens, once the stimp reading is above 11', we're already at the max value for the bogey player, therefore little or no change in the slope.
That looks somewhat consistent with our numbers. The rating difference was .3 in rating and 5 points of slope from 6700 yards and .5 in rating and 5 points of slope from 6300 yards. It essentially adds a shot to your handicap in my high single digit index range.
There may have been some adjustments independent of green speed. Slopes in Minnnesota seem to be going down. Historically they have seemed higher than slope ratings in other states.
Does anyone know whether or not the current rating methodology (hypothetical scratch and bogey golfers playing an effective playing length adjusted by obstacle factors) has been tested against actual scores to determine whether or not they in fact accurately predict scores? I would be interested in such data because it seems to me that the current system applies a number of assumptions that are inconsistent with the real world (e.g. developing slope based on a scratch and a 20 handicap golfer, assuming a scratch golfer hits the ball 250 yards and a 20 handicap golfer hits it 200 yards). The accuracy of the assumptions do not matter in the end if applying them results in accurate numbers.