Remember that a "normal" car with 3000 miles on it, has actually had the motor turning for many more "miles" of idling. ONE reason for the FEH having a larger interval is the lack of idling when the engine shuts down. The oil is also partially synthetic which makes it more stable from breakdown.

The "severe" schedule on a normal car I've always wondered about. Is driving around in the city that much harder on the vehicle, or is it that there are more miles on the oil that havent been counted by the odometer. Farm equipment always had "hours" on their odometers.... If you think about it, cars should too.

Clearly the hours/miles thing isn't the full reason for the increase to 10,000 (I don't think anyone is going around with their motor running only 1/3 of the time)

I'll bet 10,000 is just fine, but do whatever makes you happy. I just follow manufacturers recommendations myself.