Archie,
I like fall-away greens, too.
Maybe Tom Doak is right about American golfers hating them, otherwise there'd be more than a few, wouldn't there?
Two places I've played where I noticed a fair number of fall-away greens are Ganton and St. Andrews Beach.
I like it when fall-away greens are coupled with other features and elements such as:
1. False fronts or dead ground. This reduces the margin for error considerably and really makes you think; and
2. Shortish holes or holes where the approach is short. Fall aways play to an interesting fear, this fear of going long, and if the green comes at the end of a short hole it gets you thinking about which shot to hit, a half-wedge or running pitch. Either way, you have to finesse it, and small-muscle shots are choke hazards.
A fall away green on a shortish par 4 puts you in a situation where you might go from an all-out shot like busting a driver to a "whoa" shot where you're worried about going too far. Come to think of it, a green like that on a short (driveable) par 4 is going to get you thinking hard, too.
I guess what I'm saying is fall-away greens can make a short hole very interesting. (And challenging!)
Jon Wiggett on one of the Ganton threads makes the excellent point that all the stuff going on around Ganton's greens (fall-aways, false fronts, bunkers, dead ground, and, especially F+F) introduce the "idea of the deliberate miscue being a good option."
I bring that up because maybe to make a fall away green "work" there needs to be a legitimate punishment for going long; otherwise, you could just play your approach shot long / longish and mostly take out the fall away, false front, etc.
St. Andrews Beach has a fair number of fall-aways, and if I learned anything from those it's that sometimes the fear of going long is justified. The 2nd is The Little Baby Hole of Death. I liked it very much but unfortunately can tell you all you want to know about what's behind it...
Mark