Not long ago I played a course where the greens were very slow.
Without being precise, let's say in the 7-8 category.
I walked off the course thinking that it would be difficult to three putt any of the greens.
Then, I recalled playing a course where the greens were 10+ and how precise my reads, and pace had to be, not to mention executing the proper line.
In short, at 10+ on this course, the greens were "singing".
And, putting was just one of the challenges they presented.
Approach shots and recoveries had to be more carefully thought out...... and executed.
I remember one hole, a par 5, where the pin was cut far right and I had slightly mishit my approach, such that it had a little cut on it. Even though I landed my approach to the left of the hole, the mild slope on the right side of the green, acting as a catalyst, sped my ball on a journey that ended up off the right side of the green by a decent margin.
I knew the green was sloped from high left to low right in that section.
I knew to hit my approach to the left of the hole, but, a marginal error led to the de-greening of my ball.
Had that green been putting at a 7-8, I would have had a birdie putt of no more than 10 feet.
On other holes, I had to navigate ridges with precision if my approach/recovery didn't end up on the hole side of the ridge.
Again, with greens at 7-8 this would have presented no problem, but, at 10+ it was a wonderful challenge.
I had to get the line and the pace just right, otherwise the ridge would deflect my ball into three putt range.
We complain about the need for speed, but, on greens intended for or capable of accomodating speeds of 10+, why wouldn't you want that challenge at the green end ?
Let's ignore cost for this exercise.
The insidious nature of greens at speed is really, really neat.
Understanding Arthur Weber's treatise on reasonable green speeds, why wouldn't you want fast greens ?