The walk at Cape Breton Highlands is the longest one I've seen that was meant to be walked. I thought that was genius ... you are in a National Park there, and it's an enforced break which makes you appreciate the setting. [So, turning it into a cart ride is awful.]
Long cart rides like the one Brad described are pretty bad. Another course that has a few of those is Peninsula Papagayo in Costa Rica ... there are a couple of rides which must be 1/2 mile and a couple hundred feet uphill, too. There probably wasn't any other solution for that property, though.
A good routing for a golf course is all about trying to avoid awkward transitions between holes, just as much as it is about finding good holes. But, you have to keep your mind open to the possibility that a relatively long transition will be worth the walk, as opposed to other possible solutions for a particular stretch of land.