[PaleMelanesian]

I totally agree about, "the longer the coast the better the mpg gain." It's all about maximizing the glide. I often pulse uphill so I can glide down the other side.

Higher speeds: Here's where we get into YMMV territory. My car, at 70 mph, is running 3200 rpm. There is NO WAY to make good mileage in that zone. Your automatic, I assume, runs a much lower rpm. That's half the battle right there. The other half is aerodynamics, which will still hurt you. The extra speed at the top end costs you more on the pulse, and gains you less on the glide. Whether the total is good enough, or bad, depends on the specific case - ymmv.

I find the best results in the 55-60 range in my Odyssey, dwl or nearly steady speed. I haven't been able to do better with any other techniques.