Tim,
Based on my one trip around Cape Arundel a few years ago, I would say he held to his principles. I was surprised at how modern (except smaller) his plateaus in about 3 or 4 greens were, and he had some with punch bowl features, with most gently rolling. I didn't know he had written about his perfect balance. Stylistically, I would say the outside surrounds gave it consistency. The different contours didn't really "Jar the liver" as my Mom used to say.
BTW, I don't think his list of green types is all that unusual. 100 years later, its similar to mine.
Pros tell me they don't like plateaus in greens all that much and 3 (one each par 3,4,5) or 4 max is enough.
Many architects use one or two flat greens for variety and one or two wilder ones for the same reason. I try to include "planed greens" - i.e. no variation in slope, one each pitching all left, right, or back) on most courses.
I agree that most should be gently rolling, with a variety of slopes, etc. In the end, gently rolling greens do best at providing a different putt every day (combo of pin locations and random variations in shots in) without sacrificing pin locations, as per another thread. Generally, a putt of 20 feet is about twice as difficult as one from 10 feet, so there is some proportional reward for hitting it close (not always the case with plateaus in greens, which can spin a close to the pin shot back many feet, and even off the green!)
All of which confirmed my initial reaction that Travis had it going on! As Jay Morrish said often, everytime you think you are doing something new, you find an example of someone who has done it decades or centuries ago.