Hey Jim nice to hear from you. I agree I would have lost something maybe a mile or so a gallon. I only used FAS between 4-6 times per 50 to 60 mile run depending on if I made the lights, so in my case it probably wouldn't have been too bad. No battery and used no FAS on the fixed course at insightfest. I'm coming for ya Jim! lolHi chinup. Great to see you post again. Enjoyed our conversations at 2016 Hybrid Fest.
I can't quite agree on the FAS circuit thing. I think that using the FAS circuit makes a significant difference, but not sure of exact percentage.
The reason it matters is that when you "key off" you are losing the benefit of some of those "free" coasting 100s of feet. Seems to me that one can coast a 100 feet or more while the car goes through its engine off sequence. The odometer doesn't accumulate distance when the key is off. Since fuel economy is distance/fuel, the distance number becomes diminished. I first noticed this at one of Mike Dabrowski New England contests, while using key off, when my accumulated mileage came in short of the actual course distance. How big is the error - I don't really know, but since it is taken out of the "free" distance I think it is significant.
As Lyger says, it is all a game this hypermiling. Like any other game, some of us enjoy it while others think it useless. AND, circumstance of terrain, temperature, etc. vary so widely across this country that comparisons between individuals is really tough. It pays not to get too excited unless it is a regulated competition over a fixed course with some rules of competition.