As Ken Venturi once observed, slow greens tend to favor the better putter, especially on flat/uphill putts as you need a better stroke on them as opposed to fast greens where often times you just have to get the ball rolling and hope you picked the right line. He didn't mean stupidly lightening fast greens and, given my shaky putting stroke, experience says he's right.
However, slow greens are much easier to chip to (at least for me) as distance is more important than precise direction in most cases.
Having said that, really shaggy greens aren't much fun for anybody although you don't see those around much, anymore (at least not in the NE).
It is my opinion that many, if not most, Golden Age greens are now kept MUCH too fast. The contours simply were not intended for anything much above 6-8 - who could have imagined in the 1920's that those speeds would ever be possible?
I've heard that C&C told the folks at Easthampton that they would build them the awesome green complexes the club requested ONLY IF the club would pledge not to maintain them any faster than 9. If that's true, it's the right thing to do. I find those greens very puttable even though they are quite "creative".