Poor ba$tards,
my Chinese wife is a Vulcan-like creature of pure logic when it comes to any operational or financial decision. (That's even somewhat unique among the chinesey women, but thrift is a universal virtue in that culture...) We swap vehicles daily based upon who will put on the most miles.
USMC- Are any emotional connections possible, like making her car last longer, less likely to scratch something, or just feeling calmer during one's daily journeys? My wife reacted with great concern for her "baby" the first time I made her Civic downshift 2 gears on an uphill highway- she had never pressed through the resistance 'step' to the second half of pedal travel!!
I usually lose to her on MPG comparisons though, because pulse-and-glide conspires with my inner street racer, and blood must be pooling in my ever-heavier right foot on long highway drives (or something like that), while she always stays slow n steady with zero over-analysis or strategizing.